This isnt gonna be pretty. But guys i need advice. :l Okay, so..

This isnt gonna be pretty.
But guys i need advice. :l

Okay, so.. i found out that my boyfriend cheated on me. Or i guess its not really called cheating. But, this is what happened. I was looking at his page, and i was reading through some of his comments, and some were like, him flirting with this girl saying he loved her how cute she was and how she was the only one for him. :/ it like stabed a knife through my heart. The message was sent around early july late june so its kind of old but it still hurts. Especially when our relationship was so strong then. He told me he only wanted me only loved me and so many other things i now believe are all lies. We got in this big fight about it yesterday, he said it was a mistake that he was preparing himself if i left him cuz he didnt want to handle the hurt of me being gone. He kept saying it was only one time and he'll never do it ever again. I dont know, should i believe him? I told him earlier today i just wanted to be friends and id see how i felt at the end of the day. Honestly, my heart is like breaking. I love him so much, but my pain and hurt is covering the love. I lost all the trust i had in him and some of the love, and he knows this i told him. I told him we should just stop talking, and he usually fights for me when i do this. But this time he just said some things and agreed. Thats when i realzied i really love him and how much it hurts me. He hurt me alot. But he was the best boyfriend. My heart hurts, but i love him. I dont know what to do. Should i give him a second chance and see what happens?

Im scared if i give him another chance he'll hurt me again, but i still love him. :/ i dont know what to do.
PLEASE someone comment. I need help. PLEASE im begging.