Easier said than done

Co-parenting amicably with your ex can give your children stability and close relationships with both parents–but it's rarely easy. Putting aside relationship issues to co-parent agreeably can be fraught with stress. Despite the many challenges, though, it is possible to develop a cordial working relationship with your ex for the sake of your children. With these tips, you can remain calm, stay consistent, and avoid or resolve conflict with your ex and make joint custody work.

http://www.helpguide.org/mental/coparenting_shared_parenting_divorce.htm

Peaceful co-parenting certainly IS possible - anyway, both parents, especially when they've reached a certain age and are no children themselves anymore, have got the necessary maturity to control their own feelings, and, above all, put their children's interests ABOVE anything else, including themselves.
My ex-husband and I had a, let's say, relatively peaceful divorce 10 years ago (when my daughter, now 13, was still so small that she doesn't remember many things from then; one of the reasons I insisted that we divorced AS SOON as we saw that we couldn't get on together!); we settled everything, from the alimonies to the question of the various household items - but FIRST OF ALL, of course, we settled the question of how we would provide a more or less 'normal' life for our daughter, even if Mom and Dad would live in two seperate houses.
Well, we put our egoism aside, decided that I'd get the custody and he the right to visit her whenever he wants; and we even agreed that we'd spend holidays like Easter or Christmas together, providing a nice, warm, secure atmosphere for her - and that's what we still do. In the beginning, of course, it wasn't too easy, with the hurt feelings being still in our minds; but with the years, my ex and I have become the best of friends, we often talk on the phone about politics, about sports, about various subjects - and of course, our mutual goal is, now that our daughter is at the height of her puberty, to make a common try to help her get through this difficult age... With just a LITTLE bit of good will, EVERYTHING'S possible!!

Best,
Bina