Q: I have been dating a man for about a year who is quite good friends with his ex. They shared the children as they grew up and now that the kids are adults, the parents have quite a friendly relationship. My problem is the ex is getting married and has invited my boyfriend, and of course, he has asked me to join him. I’m a little uncomfortable with the invitation. I don’t care if my boyfriend goes; I just don’t want to get too friendly with his ex. What’s good ex-etiquette?

A: Since you were invited as your boyfriend’s guest, it’s quite easy to decline this invitation with an “I already have plans” excuse. However, I want to alert you to the fact that this is probably only the beginning. If these parents are friendly, you will probably be attending Mother’s Day and Father’s Day celebrations, and the kids will invite both parents to their homes for Thanksgiving and Christmas. Once they have children there will be grandbaby birthdays and other holidays — all spent with the ex. So, although it would be fine ex-etiquette to not attend the wedding, there are two very important reasons why you should attend:

First, your boyfriend has asked you to accompany him. You may not realize what a big deal this is. He is going to the wedding of his children’s mother and he’s going as a couple — with you. His kids will be there. His former relatives will be there. Family friends will be there. He is making a statement by asking you to go with him. If you do not attend at his side, I think you will be missing a huge opportunity. Take a look at what you are saying, not only to him, but to family and friends, if you stay home.

Second, good for you for not asking him to stay home. He obviously has a relationship with his children’s mother and if he has been actively interacting on this level prior to you entering the picture, he should continue to interact with her on the same level now. Beware of a red flag: If exes are too friendly it will not only make you uncomfortable, but also give his kids a false hope for possible reconciliation. Of course he may want to pull back somewhat since you and he are now the primary relationship, but not so far back that he changes the way he celebrates with his children. Both parents need to be especially conscious of their behavior.

Finally, it’s understandable that you may not want to be friendly with the ex, but take care that when you do see her, you do not openly snub her. The last thing you want to do if you want to be close to your boyfriend’s children is be unkind to their mother.

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