Is it normal to be friends with an ex?

I am really good friends, to this day, with the first guy that I dated (and broke up with) for two years. A few months ago, I went through a messy breakup from an almost two year long relationship. Things were infinitely more complicated and messy. Now, five months later, we’re both seeing other people, yet he is insistent that we try to be friends. It worked the first time, but I just don’t think it will work again. Come to think of it, I don’t know many people at all who are good friends with their ex-partners.

He wants to have dinner next week when he is in town, and I just don’t think that is a good idea. We both still have mixed feelings, but are in new relationships. (Yes, it probably was a bad idea for both of us to move on to new people before getting over the last…) Regardless, it is what it is. He says he wants to salvage some sort of good from a bad ending. I think it’s best to cut ties and move on. I only see bad things, and hurt feelings, and mixed emotions coming from an ongoing ‘friendship’ riddled with jealousy, passive aggression and hurt. Any similar experiences?