He's not your husband anymore, but he's still in your life. Experts explain how a parent can get along with her ex—while staying sane.

Break-ups are never easy. They’re even more challenging when kids are involved. So we’re fielding ex etiquette questions from parents below so you can embrace (and appreciate) your new normal.

Q. I love my in-laws. I divorced their son, not them, and they're still my kids' grandparents. What's the best way to maintain my relationship with them?

A. Your children are very lucky that you feel this way. You're right that the kids need to stay close to their grandparents even after divorce. But of course your relationship with your in-laws must change. The piece of ex etiquette to remember is to shield them, as you do your children, from any anger you may have toward their son. And tempting as it may be, avoid asking your in-laws to side with you against your ex. He's still their son, no matter how far out of line he may get. Finally, don't expect that you'll be included in every family event. That doesn't mean, however, that you can't acknowledge holidays and birthdays and otherwise show your in-laws that you still care about them.

Related: 4 Tips for Successful Co-Parenting as a Stepmom

Q. Since the divorce, some of our mutual friends have stopped calling me. What can I do about people who have taken sides?

A. Being abandoned by friends has to be one of the most painful parts of divorce—a rejection just when you're already feeling terribly lost and vulnerable. It seems personal, but it probably has more to do with the fact that married people get rattled when their friends divorce because it makes them question their own relationships. So they avoid their discomfort by not seeing you. Or it could be that they can't figure out the logistics—if they invite you, should they not include him?—so they take the coward's way out. If you've reached out to your old friends, and they haven't responded, it's probably time to move on. They may sort things out eventually and come back to you. (By the way, have you heard about collaborative divorces?) In the meantime, invest your energy in friends who have been loyal to you and in making new ones.

Q. My ex is throwing our son a birthday party—and doesn't want me there. My son wants me to come anyway. What should I do?

A. By excluding you from the party, your ex is asking your son to side with him. Naturally your son hates being put in that position and is trying to evade the conflict by asking you to crash the party.

Unfortunately, that's not the best way to go in the overall ex relationship strategy. This struggle is between your son and his father, and, sadly, you can't fight it for him. Calmly encourage your son to talk with his dad. Suggest he say, "Dad, I appreciate the party you are throwing for me, and I want you to know that it's important to me that my mother be included." Dad may rant, fume, and finally go along. Or he may flatly refuse, leaving you to celebrate your son's big event in some other way, at some other time. Just remind yourself that you're not the one who is disappointing your son.

Related: How to Get Through the Holidays with Teens Post-Divorce

Q. My new boyfriend wants to go to my daughter's soccer games with me, but he and my ex-husband have never met. How do you think I should proceed?

A. It would be better if your boyfriend and your ex break the ice privately—perhaps at custody swap time. That protects your daughter from the awkwardness she might feel having the meeting take place in front of her teammates and coach.

In your understandable eagerness to form a new family, don't forget that your daughter has half her heart deep in the old one. See what her comfort level is. Does she start conversations with your boyfriend and want to include him in family activities? Or is she polite but distant, tagging the new entry as "Mom's friend, but not mine"? Don't push public activities until you're sure your child is ready. Instead, let them develop their relationship at home, where no one's watching.

With some kids you can ask directly. "Bob would love to watch you play. Would it be okay if I brought him to the game Saturday?" A kid who sounds grudging or goes silent is reluctant. One who smiles and offers tentative approval, like, "I guess so" or "Well, tell him he can come if he wants to, but I'm not that good," may be telling you she's happy about the attention from your new partner.

Q. I still feel sexually attracted to my ex. Truthfully, we've hooked up a few times since the divorce. Why can't I just let him go?

A. It's not surprising that you'd still feel a pull toward your ex. Old emotional habits don't disappear the moment your relationship changes. It'll help you to move on with your life post-divorce if you start talking to him only about financial and parenting matters; resist being drawn into intimate conversations. You can be friends later, after you've developed a new, cooler relationship. Similarly, avoid situations that might provide a sexual opportunity. As long as you continue to put your ex in the role of man in your life, you won't have room for someone new.

Q. My ex bad-mouths me to my daughter. How can I counteract that?

A. There are two kinds of bad-mouthing as you consider ex etiquette: distortions of fact and attacks on character. Simply ignore his distortions of trivial facts. It doesn't matter when you told him about the school play or if you really sent over the baseball shirt and he forgot where it was. Your kids don't want to replay your battles.

If your ex is distorting serious facts—saying you had an affair or stole money when you didn't—counter with a short, calm explanation. When your daughter blurts out, "Daddy says you're trying to steal his money so he won't have enough to take me on vacation," simply explain, "I would never steal from your father or anyone else. Your dad is mad at me, and when people are mad they say mean things. This is one of those times." (Check out how to handle more tough family topics.)

Regarding remarks about you as a person, do your best not to take the bait. When your child reports, "Daddy says you're a witch," take a deep breath and respond, "Daddy must have been in a terrible mood to say that." Then change the subject. Counteract his bitterness with your own loving fairness, and your daughter will form her own opinions about you.