Avoidant ex friend group help

He broke up with me in November unexpectedly (although he had been pulling away so not completely a surprise) and I’ve been struggling with maintaining the friend connections I found through his friend group. I attended a few parties since then that he was at and I feel so uncomfortable and unresolved that I leave early and feel depressed that I can’t hang out with my friends without getting upset by him. I’ve been thinking about reaching out to try and have a cordial conversation with him away from the group dynamic just to break the tension and maybe help me feel less anxious to be near him, but I’m worried that’s a bad idea. Any advice navigating this dynamic?