Sandrawg, if he knows your history and why this would be hard for you and has chosen to forge ahead anyway it sounds like there is a real problem.
Have you sat down and done a face to face with him or was it strictly email If you have done the face to face and he is still blowing you off, then you are right it is decision time; as for me I am the suspicious type, my ex wife cheated on me for a long time when she supposedly working, so now I am more inclined to think space = cheating.
Are these all guy friends and he want to do every Friday night with the guys or is it a mixed crowd, if it's a mixed crowd my radar would really be up. If it were me I would send a couple of my girlfriends he has not met into his hangout to do some recon.
Anyway you know the drill, the only person that can control your feelings and reactions is you.
I hope it works out for you, if you want to talk, need to vent, or just want someone to lean on I will be here for you, I also do a mean cyber bear hug with extra parenthesis.
If I can help I will, best of luck to you.
Bill