I was told he cheated. Who to believe?

So earlier today I got a message from a girl I'm not really friends with and also a guy my boyfriend is friends with and they both told me he cheated on me with this girl we both know. I am devastated. I don't even believe it. My boyfriend is as close to perfect as a man can get. I love him with all my heart and I never thought he'd do this to me. He was texting me all morning and I couldn't respond to him because I didn't know what to say. He called and I couldn't verbally speak so I ignored it. He came over to check on me and denied it obviously but I was an emotional wreck. He was too. He started crying and saying he'd never do that to me and he'd do anything to prove it. I am in a really tough spot. I have been cheated on twice before and this is just ruining me. I want to believe him but it's hard to. I don't know what to do. Help? Thank you.