I am on reasonably good terms with my 2 most recent exs. One even came to my wedding and phoned me from the hospital when his first child was born.
My ex who I was with for 7 years and I split up 3 months before the wedding when he left me for another woman. I don't resent him or her, our relationship was rubbish. We had nothing in common, I didn't fancy him and he was boring. He's a nice bloke though and i wish well.
On the other hand my husbands ex is an evil [cow] who I hate and so does he. I used to be friends with her so she's an ex (friend) of mine too