I need help

I have a boyfriend...and we have been on and off for three years...this last time we got together has been a full year. I love him so so much. However a few days ago I figured out something. There is this girl...I'll call her Jane. Jane and my bf were really good friends. I was always suspicious about her because she did things that threw me off. Come to find out i was kinda right.

Around September, they were at a party and her friends had talked them into kissing each other. He says it was a peck and that he did it because he was peer pressured into it and didn't want them to make fun of him. They cut off all ties and don't talk to each other anymore...but still. He waited so long to tell me.

It hurts. I still love him so much and the thought of being without him again makes me feel so hopeless and numb. I know I sound ridiculous right now and naive but I can't help it. He is my first for everything and I can't just let that go.

We agreed to just try to forget about it but everything just feels off. I'm trying hard to remain calm without crying but I feel like everything I do is wrong. I feel like I'm too clingy and annoying. He assures me that im not but he seems so distant. He doesn't call me the way he used to and just doesn't she as much love and as im typing this I feel as if he doesn't love me....