Help!! Sex problems...

I recently started dating a new guy and we immediately connected. We really get each other and the sex was just amazing. The other day we were making out and everything was going great but then he couldn’t get hard. I thought it was not a big deal but he seemed really concerned and he told me it had never happened before. After that night, we’ve tried to have sex again and he can’t get hard or he gets hard but as soon as we start having sex, he loses his erection. We have really good chemistry and we are really into each other but this is killing us. He feels very frustrated and now he wants to end the relationship because he says this is really affecting him and he can tell it’s affecting me too. I have never had this issue before either but I really like him and I think we can get through this. He says he is really into me and he’s horny all the time but when we start having sex he just starts thinking about random stuff like “the music is too loud” or “these sheets feel itchy”. This has never happened before to either of us. I think it’s all in his mind but I don’t know what to do to help him and I really want to fight for what we have. Any ideas?