<human>: Before my boyfriend and I were together he slept around a lot. He had some long term-ish relationships, but not many. We are the longest relationship he has ever had, almost two years.

Also, he has a lot of female friends. Some of who he use to sleep with and/or had a relationship with. It doesn't bother me that he has these friends, but the activities they do together bother me. He is very social and likes to drink so lots of times he hangs out with these girls at bars. I can't come because of my age. I turn 21 in a few months and he says once I do he'll invite me to hang out with him and his friends too. And he says if they're not planning on going to a bar that I can come along then.

However... this doesn't seem to be the case. For example, right now he is hanging out with a girl he's friends with and they're hanging out at a house she's dog sitting at. So not a bar. He brought a full bottle of gin with him. In this case I would have been 100% able to come with him and we all could have had fun. I know this girl and she knows me and we get along. One time though when he was really drunk he tried to kiss her and that still upsets me. She wouldn't let him so that's the only reason why it didn't happen. I hate it that he hangs out with these women in private settings and makes promises of me coming along and they never happen. 

Basically, should I be worried? I mean, I am worried and it makes me so sad that he chooses to drink privately with women he was or wanted to be intimate with. Is this normal behavior? Am I overreacting to the situation(s)?

Can you summarize the given text in a few sentences?
<bot>: Boyfriend hangs out privately, drinking with women he has slept with or has wanted to sleep with. Promises to take me along, but never does when the opportunity comes. Should I be worried about possible infidelity?