So I'm seeing this guy and he is great, we get on so well and the sex is fantastic. But this last Friday we went to a party at his friends place. And they look a lot alike in general, I've always told them this and so a couple of drinks later I was dancing with his friend thinking it was the guy I've been getting with and we ended up kissing. It wasn't until we kissed that I realized that this was the wrong guy. And the worst part was the guy that I'm with saw the whole thing. I tried to explain it to him and he says he understood but I don't think he is ready to trust me again. But I really like him and I don't know how to get him to see that I only kissed his friend because I thought it was him.