I'm still very good friends with my ex. We don't have any interest in being intimate again or dating. Even when we were still together we were more friends than we were bf/gf. She told her new bf that we were still friends up front and that if he wasn't ok with it then he might aswell not waste his time with her. A lot of people think it's weird but why stop talking to someone who has been your friend for so long just because you can't make a relationship work. I'm not a jealous person so I guess that has a lot to do with it. I say let her go and trust her. If you don't trust her the relationship won't work anyway and if nothing happens and it's just dinner with an old friend then that just makes your relationship stronger.