Is it wrong of me to not know who to believe?

I'm seeing this guy who used to be best friends with my brother. A friend told me earlier that the last he knew, he still had a girlfriend (as of a month ago,) he was a pothead, and my brother had told me last year that he saw my boyfriend in Walmart, on meth. I asked him calmy, and just told him that if I ever found out for sure whether any of those things were true, I was done. Now he's mad at me. Should I apologize?