Q: I've been invited to a good friend's party. I'd like to bring my new guy, but I know my ex will be there and I am afraid he will cause a scene. Our son is 3 and I can't completely walk away from the guy, but he's out of control. He blows up my phone constantly asking me to come back, but he's the one who cheated. Our son is a mess watching all this. He cries whenever I leave and now he's having accidents during the day. Will going to this party just make things worse? What's good ex-etiquette?

A: So often the problem that leads you to ask a question is not the primary problem at all. In your case, whether to attend a party is small potatoes in the big picture. The real problem is how you and Dad are handling this breakup in front of your 3-year-old son.

Children are frightened and confused by extreme emotion. They look to their parents to be their center, their security, and if either of you are out of control, they feel out of control, as well. A 3-year-old can't tell you what's wrong, really. So, they act out, throw tantrums, don't sleep well, get clingy or have accidents after previously being potty-trained. Your son is displaying classic telltale signs of stress. That's what you need to address.

Good ex-etiquette is putting the past behind you, the kids first, and looking for ways to get along in their best interest (Ex-etiquette for Parents rule No. 1). You didn't mention how long you and Dad have been apart, but if it's months, not years, take a look at how fast you're moving on and how it may be affecting not Dad, but your son. No, you should not curb your actions to calm a cheating ex, but if your actions are affecting your child, that's another story. That means, maybe the boyfriend shouldn't sleep over right now, and you should spend as much one-on-one time with your child as you can.

Dad should refocus his angst, as well. Stop spending all his energy on getting you back and spend some quality one-on-one time with his son. Bad choices behind you — what counts is going forward in the best interest of your child.

That said, let's address the lesser problem — Party Ex-etiquette. Should you go if you know your ex is going? That's up to you, but if you both go, then it is understood both will act like adults, respect the home, and not cause a scene. Anger and hurt mixed with alcohol is a recipe for disaster. If you know in your heart that your ex will not be able to contain his emotions, consider staying home. Hopefully, time will heal some of this. That's good ex-etiquette.

Jann Blackstone is the author of "Ex-etiquette for Parents: Good Behavior After Divorce or Separation," and founder of Bonus Families, bonusfamilies.com.