Generally, the court will consider matters of custody by examining what is in the best interests of the child. The best interests of the child standard includes many factors. The court considers the presence of all relevant factors in its custody orders, and each factor, including those having to do with mental health issues, may be weighed differently from the others, depending on the individual facts of the case.
Three of the factors which are particularly relevant to the issue of medication are the factor of parental fitness, the factor of ability and willingness of the parent to care for the child, and the factor of health of the parent. Let’s examine each of these three factors below:
1. Parental Fitness and Medication
Unfitness of one parent might clearly disqualify that parent from obtaining custody of the children.
In one Massachusetts case, custody was awarded to the mother after she proved that she was dealing with her depression and emotional issues successfully, despite a short period of hospitalization. The father appealed, but the Appeals Court agreed with the trial judge, noting: “In our opinion, on the evidence before her, the judge could permissibly conclude; (a) that Marie is dealing successfully with her emotional problems; (b) that of the two parents “she despite her problems can offer the children more room for growth”; (c) that Gino has an “obsession with keeping control over the life of his wife and children” which causes much of her stress; and (d) that the welfare of the children will best be served by granting custody to their mother, with liberal and specific rights of visitation for the father.” 
Being on medication for mental health issues, then, might actually be a positive factor for the parent seeking custody, as long as the parent can show that the medication is helping the parent overcome mental health issues successfully, and that it does not affect his or her fitness as a parent.
There is a line of cases which does not directly deal with custody disputes but is relevant to this discussion: cases that deal with the termination of parental rights and the care and protection of children. In one recent appellate case, the mother was able to show that she was fit to care for her child, age nine, despite suffering from severe past trauma, ADHD, past substance abuse, and an executive function disorder. In that case, the child also suffered from several mental and emotional issues and was on medication for them. The Appeals Court reversed the trial judge’s order for care and protection of the child.
By contrast, two other cases in which the mental or emotional health of the parent was contested found that the parent in each case was unable to care for her child: in one, the mother neglected to attend necessary treatment; in the other, the mother refused to complete ordered substance abuse programs and had a history of visiting multiple doctors in order to obtain additional prescription drugs. 
2. Ability and Willingness of the Parent to Care for the Child and Medication
When the Probate and Family Court examines the ability and willingness of the parent to care for the child, it uses a balancing test—by accepted premise, the rights of each parent are considered to be equal, so the Court will balance and compare the relative abilities and willingness of each parent to care for the child. Lack of interest in the child or motivation to parent, as well as a history of not carrying out parenting tasks, will be relevant to the Court’s comparison.
Note that there are some additional factors which might be at play here and relate to caring for the child: for example, the court might look at the suitability of the parent’s residence, the lifestyle of the parent, and any abuse, substance abuse, or violence. If emotional or mental health issues have interfered with the parent’s ability to provide a safe and stable residence, for example, or perhaps escalated into abuse or violence in the past, then the Court may consider those factors. Or, if emotional or mental health issues have caused serious substance abuse by the parent, the Court again will consider that factor. However, in and of itself, taking lawfully prescribed medication for mental health issues will not disqualify a parent from being awarded custody.
3. Health of the Parent and Medication
Obviously, the physical, mental, and emotional health of each parent is a significant factor in making decisions regarding custody. In several cases, the Court considered the mental or emotional instability of a parent as a decisive factor in awarding custody to the other side. 
However, neither physical nor mental illness of the parent will automatically disqualify the parent from custody—rather, it is relevant ONLY when those issues adversely affect the child, or where the parent cannot adequately carry out his or her parenting responsibilities.
 Angelone v. Angelone, 9 Mass. App. Ct. 728 (1980).
 In re Laurent, 87 Mass. App. Ct. 1 (2015).
 Adoption of Jacques, 82 Mass.App.Ct. 601 (2012).
 In re Adoption of Sunil, 79 Mass.App.Ct. 1112 (2011).
 See Fort v. Fort, 12 Mass. App. Ct. 411 (1981); Sloane v. Sloane, 349 Mass. 318 (1965); and In re Stephen, 401 Mass. 144 (1987).
The decision to end a marriage is painful. When a spouse has a personality disorder, the road to resolution and recovery will likely take longer than the typical divorce. But for many people entering a divorce, their spouses haven’t been formally diagnosed with any mental defects whatsoever. Many more haven’t come to the realization that their spouses have a personality disorder and instead, chronically blame themselves for failing to be more supportive. Typically, the “healthy” spouse is the one bearing the burden of guilt, both during the marriage and through the divorce.
The issue of personality disorder often comes up in divorce consultations. Potential clients, while dealing with their spouses’ deficiencies for years, sometimes decades, are ready to attribute to a personality disorder as the reason the marriage has ended. While personality disorders are tremendously serious and can wreak havoc on the psyche of those in close proximity, there may be an over-diagnosis by those going through divorces. The words, “my husband is a narcissist” or “my wife is obsessive/compulsive” or “I think she has borderline personality disorder” are likely being muttered in the offices of many family law attorneys across the Commonwealth as you read this article. Of course, a personality disorder is an actual, medically defined thing.
Diagnosis of a Personality Disorder. The Diagnostic and Statistical Manual of Mental Disorders, or commonly referred to as DSM, is the manual used by clinicians and researchers to diagnose and classify mental disorders. The American Psychiatric Association (APA) published the newest version of the DSM called DSM-5 in 2013. According to the DSM-5 “Personality disorders are associated with ways of thinking and feeling about oneself and others that significantly and adversely affect how an individual function in many aspects of life. They fall within 10 distinct types: paranoid personality disorder, schizoid personality disorder, schizotypal personality disorder, antisocial personality disorder, borderline personality disorder, histrionic personality, narcissistic personality disorder, avoidant personality disorder, dependent personality disorder and obsessive-compulsive personality disorder.” Personality Disorders are Axis II disorders while more “serious” Mental Disorders (Bi-Polar disorder, Depression) are Axis I. While it’s important that you understand the technical definition and criteria of a personality disorder if your spouse has one, ultimate diagnosis should be left to mental health professionals whenever possible.
Educate Yourself on Diagnosis and Treatment of Personality Disorders. If you’re in an intact marriage and living with a spouse whom you believe has a personality disorder, you should do your research and get to the bottom of the issue one way or another. That involves educating yourself on the symptoms and treatments of the applicable disorder and encouraging your spouse to seek out help from a mental health professional. There may be, after all, a way to treat and improve the symptoms and that’s a benefit to your spouse and your marriage. As a professional knowledgeable of mental health issues and how they manifest in marriages and through divorce, I believe you owe it to yourself and your spouse to make a good faith effort to learn about the disorder and to understand how it might be combated short of ending the marriage.
Manage Your Mental Health While Dealing with a Spouse with a Personality Disorder. Nobody ever said marriage would be easy, but dealing with a spouse with a personality disorder sure can seem like more than you bargained for. But, when entering the marriage you both did it for better or for worse, so if you’re dealing with this, you’ve got a duty to try and make life as good as it can be. That includes focusing on you, too. Educating yourself also involves learning about the best ways to maximize the happiness and fulfillment in your life, while living with a spouse with a personality disorder.
Particularly because the internet houses a mass of misinformation on this subject, I encourage you to seek out a good book on point. One such book is entitled Out of The Fog, by Gary Walters. In this book, Walters opens by saying, “Living with a personality disordered individual can feel like living in a FOG. Fog stands for Fear, Obligation, and Guilt.” While you shouldn’t expect a book to resolve the issue, some initial validation of what you’re living with is a healthy first step. Seeing a great therapist is a sound second step because, although the treatments of personality disorders are very limited, ongoing discussion with as support who understands the struggle can be a key part of finding happiness.
Obviously, people dealing with the personality disorder of a spouse can reach their limit. Even very dedicated and understanding spouses can conclude that holding the marriage together is not worth the abuse. Yes, I am a divorce lawyer and I’ve now represented over a thousand clients. But, I have no interest in pushing a client to file a divorce when he or she is not ready. My role in an initial consultation is that of an educator and to be supportive and encouraging to any glimmer of hope in keeping the marriage intact. I ask every potential client if he or she has tried therapy, either couple’s counseling or individual therapy of some sort. If there’s a reasonably likely way to save the marriage, that option should be pursued before filing for a divorce. Of course, it does take two parties to agree to seek help together and sometimes one party won’t play along, never mind admit there might be a problem to begin with.
If you do believe your marriage is over and you believe your spouse has a personality disorder, seek out the consultation of an experienced divorce and family law lawyer, preferably a lawyer with experienced handling complex mental health issues. Understand the definition and symptoms of the personality disorder and explain to the lawyer how you’ve concluded the disorder exists, whether you know it to be diagnosed at any point, and how the disorder has manifested in the behavior of your spouse. Explain how accepting or resistant your spouse has been to his or her diagnosis and treatment and be sure the lawyer understands your concerns, particularly concerns of safety. Personality disorders are very real and the right divorce attorney in your case will understand the dynamic and how it will likely come out in the divorce process.
Our attorneys not only have experience handling sensitive divorce matters such as described above, but are also trained and have extensive experience handling cases with complex mental health issues. If you are living with a spouse with a personality disorder and want to get educated on your rights in a divorce, schedule a free consultation with our team by calling 978-225-9030 during regular business hours, or complete this contact form and we will contact you back at our earliest opportunity.