You are still pretty new to the process. At 4 months out, we were still wading through TT and the rubble of D-Day etc...
My H never had a group of BOYZ that he hung with but went to games and sports/bars with a few friends here and there.
I don't think he went out alone for close to a year. I/we had some social gatherings that we attended together but even those were wearing on both of us at the time.
IMO, if his friends are friends of the marriage then something can be worked out. But if he wants to get back in the routine with friends with limited boundaries who assisted in his affair then it would be a huge HELL NO from me.
There isn't 1/2 way with someone who is not willing to commit to transparency and building boundaries.
My H thought he could tell me 1/2 the truth and wait patiently(doing nothing) for me to heal on my own. We actually had an extended argument over whether there was such a thing as an "anti-versary". Like a 2 hour argument. Crazy.
Nothing much happen in R until I put my foot down, drew the line in the sand and defended it.
I tried to negotiate. I tried to see his side. I tried to be 'nice. I tried doing all the work and pushing him along inch by inch.
Nothing worked until I was willing to defend my boundaries by walking away. Nothing.
Some situations are like that. Only you can say if yours is.