Originally Posted by
Uplate 
3) he is writing his memories and somewhere he mentioned that the sex was great...which I found offensive. I set clear boundaries about that right away. He is in his 3rd marriage.
This is really bad.
Sounds to me like he wants to
get out of his 3rd marriage.
Why would he bring up, even in passing, that ya'll had great sex?
Well, nevermind, I can answer that. There IS no good reason to bring that up.
It's actually kind of disturbing. It's a clear sign that he is harboring old feelings for you and that there is a problem in his current sexual relationship.
It would be a really bad idea to give him your phone number or to continue having contact with him. If he has balls enough to bring this up in his 1st or 2nd message with you in 20 years, then, trust me (from experience), it's only going to escalate from there.