How do I even deal with this?

I've been kinda struggling lately with a crush that I have on a guy. He's in a committed relationship with someone else and they have been together for 6 years. We seem to click on a lot of different levels and literally him just walking into a room makes my day better, but I don't want to be a home wrecker. Help? I'm stuck. I've been trying to go on other dates and se other people but all the things I like about a guy seem to just be all the qualities that this guy has, and so it doesn't work out because it goes back to him. We are good work friends, but I wish it could be more than that. A few days ago we bumped into each other at a gay bar and it was honestly one of the best nights I've had in a really long time. Please help me out here reddit? What should I do?