Q: My ex and I have a daughter, plus I literally raised his three children from his first marriage. After 15 years together he ran off with someone else, but after a long and drawn out midlife crisis he has decided I'm the one. I ignore his advances most of the time, but when the tree is lit, the carolers sing, and the kids talk about the way it used to be, I long for my old life and forget what a rat he was. I'm thinking about forgiving him, but I'm afraid it's just this time of year. Have any advice? What's good ex-etiquette?

A: Each year around this time I start getting questions about whether people who have had terrible breakups should get back together. They start very similar to your question, laying the groundwork, then wondering if they should forgive the person who broke their heart and made a mess of their life — after all, it's Christmas.

I call the feelings you describe "the Christmas Crazies." It's built on what some regard as the definition of insanity — doing something the same way over and over and expecting a different outcome. (Although certainly not the clinical definition.) I'm not saying that your ex will definitely cheat on your again — I don't know the whole story, but if you are contemplating going back to him and you have an inkling it might be based on sleigh bells ringing, take a breath for a few months.

Truth is, no one likes to be alone and if life isn't all that great right now, the holidays can make you wish for the way it used to be, but be careful that you aren't romanticizing your former life. You broke up for a reason, and the kids got on that roller coaster with you. The last thing you want to do is go back with their dad, only to break up again. It's not good ex-etiquette to re-create chaos. That's not putting the children first. (Ex-etiquette for Parents rule No. 1.)

The key to knowing if it's just this time of year is to consider if you carry a torch for him all year round. If you do, then address it. Good ex-etiquette is all about being honest and setting good boundaries — not only with your ex, but with yourself. (Ex-etiquette rule No. 8, "Be honest and straightforward.") Most couples have a pattern — and they will re-create that pattern if there's nothing to prevent it. So, if there was a negative outcome, say a breakup, and you go back together, if you don't break the pattern, you are bound to re-create the former outcome — which means another breakup.

Finally, reconciliation after infidelity is not for the faint of heart. Don't just move in together to see if it will work again. Couples who are considering reconciliation must have a plan for success in place before they go forward. Consider counseling and be as honest as you can so you both don't make the same mistakes. That's good ex-etiquette for any time of year.

Jann Blackstone is the founder of Bonus Families, bonusfamilies.com.