should I believe his friend....

My boyfriend's best friend just recently told me that my boyfriend is cheating on with someone else. It's a complicated situation because his friend revealed to me that he liked me.

One Saturday my boyfriend, his friend and me planned to go out to a night club until later on in the day my boyfriend told me that he didn't want to go and that he thinks me and his friend should go. Now I felt completely uncomfortable to the point where I kept asking my boyfriend countless times is he sure that it's ok because I don't want any problems and he stated that his friend and he doesn't look at him as competition. So his friend and I went to the nightclub along with my bestfriend. We all had a great time, but that night that's when his friend was telling me all of these things about my boyfriend and how I am too good for him and I shouldn't be with him. Before the night was over his friend entered his telephone number into my phone in which I did not use it. So about a day later he made up some excuse to get my cell phone number from my boyfriend and I guess he didn't think anything of it because he gave him my number. So since he gave my number his friend calls me and I must admit we have good conversations (but me I am always talking about my boyfriend) and I also explained to him that I don't date my boyfriend's friends. So he kept telling me that he liked and he may have to back away because he's going to end up being attached. So recently he told me that my boyfriend is a cheater and two weeks ago he was at his house and my boyfriend was getting dressed and told him he was going to this girl's house to get some ass. Now my first reaction was "oh my god that's so messed up" deep down inside I was hurt. As the day progressed I thought perhaps his friend could be lying to me, since he does like me. What do you guys think?

Last night I went over to my boyfriend's house and I told him what happened. I basically told him that his friend likes me and that his friend was telling me all of these things about him being unfaithful and me being too good for him. He reacted very nochalant about it, he basically said well if my friend feels that he can get you then "hey". And for me to not get any kind of reaction from him just made me feel that he didn't care about me. Because I know for sure if it was me and my friend told my boyfriend lies about me I would be upset. He made a statement that it's all about survival of the fittest, wow! I don't know what to think now. I'm scared that I am being too naive. And believe me my boyfriend and I have been through so much where I often have my thought's that he may be cheating, however I never had hard evidence to prove that he was so I continued to go along with things just to see if my thoughts were right or wrong. What do you guys think?