I need relationship advice!

I've been with my boyfriend for 2+ years. When we first started dating (like everyone in a new relationship) we were having sex multiple times a day. But now I don't want sex at all. I don't even want to kiss or make out. We talk about my sex drive all the time and it starting to take a toll on us. He blames himself, I feel guilty and the cycle continues. I've had a low sex drive for maybe 8 months now. My doctor said it could be antidepressant medicine and that when I stop it comepltely (about a month to go) my sex drive should increase. Also, I feel more guilty b/c I'm also thinking of kissing other people. I can't stress enough that I would never ever cheat on him. I just can't help thinking if there's more out there. I'm really young and sometimes I wish I met him later on in life so I could explore other people and my sexuality now. I would appreciate any advice or past experiences!! Thank you!!