I'm very very good friends with my ex boyfriend. We see each other a lot (I'm the person he sees most during term time) and are very close. One month ago he got back together with a different ex girlfriend (when he was with her before, he did cheat on her with me before ending it to go out with me). I am really happy for him, and although it hurt first of all, our friendship is stronger than ever (closer than when we were together) and I've moved on. Two days before he got back with his girlfriend, him and I spent the night together (no sex just pulling etc). But, some aspects of our friendship never changed from when we were going out to now, eg he rings me about things he should really be discussing with his girlfriend and we're still quite touchy feely. Last night in a club I ended up with a guy and my ex was also there, a close mutual friend of ours told me that he got very very jealous of me with this other guy.
So I'm wondering at what stage does a friendship become inappropriate with a friend of the opposite sex who has a partner?
We have discussed going away just me and him over the summer as his summer holiday and whilst I would love to go away with him (as he is one of my best friends) I'm just wondering whether its really appropriate?