I personally don't mind going to bars, as long as there's no smoking. I just grab a water and chat. Plus, DH likes that he has a DD! =)
However, I do know how you feel. 2 of my best friends up and left after I got married. I never got a clear explanation as to WHY, but they just stopped talking to me. I can only assume that they weren't ready to grow up and I was. When I stopped going to bars every weekend with them, I guess they started to feel like I wasn't 'cool' enough to hang out with them. Looking back now, they werent as great of friends as I thought they were and Like someone else said, some people can't handle change. You'll find new friends. =) Good luck!