However, if either of you is attached, I'd suggest not even coffee. Not even emailing. I am biased, because I talk to people where things have gone wrong, but I am amazed how high a proportion of marriage breakups now seem to start with "getting in contact with an ex" on facebook or email. It's a lose/lose scenario - you either don't hit it off this time, or you do. Just my opinion.
I'm with you on this one Mike, very much.
Ex- boyfriends have tried to catch up with me in various ways, FB being just one. I know, knowing my exes that it's not innocent.
I wouldn't like D meeting his ex wife for coffee, even though I trust him completely. And so therefore I wouldn't do that to him.
Plus I'm generally not curious at all about people that I've moved away from. Not at all.
So I'll echo the statement that if you're unattached, fine, otherwise, don't bother....