My boyfriends friend keeps accusing me of cheating......

This morning my boyfriend texted me that he had a bad dream. It was that I left him for another guy. I told him I loved him and that he had nothing to worry about. He said that he does worry because he hasn’t seen me since covid started, but refuses to get tested. I do not feel comfortable meeting him at his house because his house is crowded. He lives with his roommate and older brother who invites over girls from dating apps, his girlfriend, and his friends weekly. So I said it’s best if we FaceTime/call each other in the meantime and everything has been fine.

Later in the day he calls me from work telling me his friend Matt he thinks I’m cheating because I’m not coming over. So I asked him did he also tell Matt that he refuses to get a covid test? He said yes, which I find hard to believe. If he did why would his friend accuse me? I messaged his friend Matt on Facebook letting him know what he said rubbed me the wrong way and that I would appreciate if this did not happen again. I also sent my boyfriend a screenshot so his friend could not twist my words. He texted back he saying “Babe stop” then I noticed the Facebook message was left on read and his friend wasn’t responding. I called my boyfriend and he kept asking if Matt said anything, I said no. He said he told Matt he needs otherwise they can’t be friends. I asked for a screenshot of everything said because I sent him one and he refused telling me he deleted everything. If he truly trusted me why pretend as if you had a dream I cheated instead of being upfront and saying your friend is gossiping and that he believes it?