Q: My fiancé and I broke up for a short while, but we have reconciled about three months ago. His ex-wife continues to ask him out for coffee, dinner, to join her skiing. Now she has asked him to join her in Cabo with the kids, and I hit the ceiling. It's really maddening, and she won't stop! What's good ex-etiquette?

A: Although your question sounds like "How can I get my fiancé's wacky ex to stop coming after my guy," it's more about your boyfriend having blurry boundaries and not being honest with everyone concerned (ex-etiquette Rule 8: Be honest and straightforward).

No one continually invites someone somewhere when they know they'll be turned down, so something has given her the impression she might get a different answer. I don't know what happened during that "short while" when you broke up, but if she's acting differently now than she did before your moving out, it's time to talk to your fiancé. If this is the way she has always acted, it's still time to talk to your fiancé.

It's his responsibility to set clear boundaries, so his ex understands where she stands. He might like all the attention — or he might feel that letting her think there is something between them will enable him to see the kids more often. You're playing with fire when you play with the affections of your children's other parent. And, although it sounds as if you don't think reconciliation is a possibility, she seems to.

Even if it's all an innocent misunderstanding or the fact that he doesn't like confrontation, it's still his responsibility to take control of the situation. His kids are watching how he's handling all this. The more he vacillates, the more they will be placed in the middle trying to figure out where their allegiance should lie, with mom or dad. (Ex-etiquette Rule 1: Put the children first.)

Bottom line, whatever your fiancé's motivation, he must address this. That's good ex-etiquette.

Jann Blackstone is the founder of bonusfamilies.com.