Q: I’m a single mother of two beautiful children. I have been in a relationship with my boyfriend for just over a year. My children and I live with him. He was in a relationship with a woman for 20 years and separated about three years ago because of her affairs. They weren’t married, but they do share a grown son — and I know my boyfriend misses the family time. I’m trying to get along with his ex for his son’s sake, but she’s very inappropriate. She kissed him on the lips several months ago and said she misses his lips. About a week ago he hugged everyone goodbye, including her, and she made it a point to call him on his way home and say she could smell him on her shirt. She is nice to my face but obviously wants him back. I’m trying to be patient. I don’t want this to get ugly. What’s good ex-etiquette?

A: I’m not so sure she does want him back. She has a history of infidelity and it sounds like this may just be her MO. However, it’s up to your boyfriend to clarify the boundaries and make it clear he’s not interested. Their son is an adult, and the family birthdays and school activities are bound to have slowed down, so there’s not much reason for the ex to be around. After 20 years it’s understandable that your boyfriend might miss the family time, but he can’t possibly miss the cheating, so it’s time to figure it out, make it clear to her where he stands, and do his best to find family time by integrating his son into his life with you.

In his defense, one year is not that much time into a new serious relationship and the weaning process from past to present may be more difficult than he first suspected. It’s good that you are patient, but keep your eyes open. Her actions are way out of line. Good ex-etiquette does ask you to be open, honest, and straight forward — but not stupid.

Your situation is the exact reason I stress that you must know where your relationship is going before you bring your children into it. If you would have had a clear commitment, there would have been no question as to how he should handle an inappropriate ex. Have the conversation now, and both must be clear what is expected in the future.

Dr. Jann Blackstone is the author of “Ex-etiquette for Parents: Good Behavior After Divorce or Separation,” and the founder of Bonus Families, www.bonusfamilies.com. Reach her at:

drjannblackstone@gmail.com