Crush troubles

So here’s the dealio. I have hella feelings for basically my best friend. He knows and we’ve talked about it a few times. Except he has a girlfriend that I’ve never been a fan of even before they started dating. I’m not gonna try to rip them apart bc wow that’s mean. Him and I hang out so much it’s hard for anyone to believe I’m not his girlfriend. I want to step back and separate myself so I don’t get even more hurt. How can I do that without being mean????