While some extramarital affairs go on for years, these relationships are typically short-term, explains licensed clinical social worker Kristina Randle. If you develop a strong attachment during your affair, this can lead to significant heartbreak when the affair ends. These feelings can be even worse if your married boyfriend made promises to leave his wife. During the relationship, you may also feel hurt, angry or anxious because your boyfriend is involved with another woman who has a legal claim to his attention and time -- his wife. Additionally, if the married man you are dating has children, you will likely cause emotional harm to not only his wife, but his children. Indeed, Dr. J.R. Bruns, the medical director of the La Mer Integrative and Behavioral Medical Group, explains that married men who have affairs often become disconnected from their wives and children, leading to further distress and damage in the family system.

If you respect the institution of marriage, an affair with a partnered man means compromising your values. In an article for "Psychology Today," psychiatrist Mark Goulson points out that when you date a married man, you are helping him betray his wife as he turns against the promises he made when he married her. Additionally, Mark White, chair of the Department of Philosophy at the College of Staten Island/CUNY, explains that from many philosophical perspectives -- both secular and religious -- adultery is almost always wrong because it involves deception, hurting others and breaches of commonly-held social values, such as fidelity and honesty.

It is unlikely that a married man can meet all of your needs and expectations. For example, it is unlikely that he will be able to spend holidays with you, meet your family or be there for you during sudden crises. Likewise, married men typically have to schedule time to be with girlfriends around the schedules of their wives and children. This means that your married boyfriend will almost always call the shots when it comes to dates, which can be disempowering. Further, WebMD explains that while most women seek out affairs for emotional connection and validation, many married men prefer to keep extramarital relationships physical rather than becoming close emotionally.

In many cultures and social circles, people treat “the other woman” scornfully. Even if your friends and family support your decision to see a married man, your colleagues, acquaintances and others you deal with in your daily life may make negative judgments about your character if they find out about your relationship, potentially straining friendships or even limiting job opportunities. Additionally, if your boyfriend’s spouse finds out about your relationship, you may be brought into the couple’s divorce case, which will be stressful for you and may damage your reputation with others if your personal relationship is examined as part of the court proceedings.