Balancing my friends and my boyfriend..help?

I am a very social person and have many friends. People bring out different personalities of me. With my friends, I am loud, funny, and obnoxious. With my boyfriend, I am sensitive and more reserved because he has some antisocial characteristics. My mom noticed that I'm even more reserved when I'm around him when we went out on the weekend. My boyfriend confronted me today that I seem to have more fun with my friends whenever he happens to see me. The thing is, I have great friendships with my friends cause I've known them all my life...so of course I'm very, very comfortable around them. I've told him that too. They also want to get to know him, but, he seems close minded because he feels like the outcast. I don't know how to get him to get to know my friends because I also miss being with my friends too. I've fallen head over heels for my boyfriend, but it's also tough balancing my friends. Help?