Low Sex Drive?

Ok, I've been with my boyfriend for about 3 months and he and I used to never really have problems when it came to the bedroom activies. We always try new things and try to keep it interesting, but lately my want for sex is gone completely.

Its not that he's bad in bed or anything but its just become something I don't look forward to. When I lost my virginity last year, sex was literally all I thought about. I tried considering maybe it was my ex that took my virginity that made me feel that way because he was just better in bed but I can't seem to find any real differences between him and my current boyfriend.

Also, I've had sex with 3 people and the person I lost my virginity to was the only one who could make me moan.

Lately my boyfriend and I have been fighting more and more about this and I don't know what to do, please help!