We've been working together for a year and I've always been attracted to him. We worked different shifts so we didn't see each other for awhile. Now he works the same shift as me and we've been talking and flirting a lot. He's a great guy and I can tell there's something between us. He got out of a relationship and it was a bad one. His ex was abusive, physically and mentally. We call each other best friends and I'm not sure how to make it more?