I like this guy i work with...?

If you are feeling something about this other guy, you may want to reexamine your relationship with your bf. Maybe consider counseling, take a weekend away together, remember why you got together in the first place and see if the spark is still there. If its just not there anymore, and you truly care about him but arent in love anymore, its not fair to him to keep him around, he should be freed to try to find someone else who can love him back. Just don't flirt with the doorman in the meantime, it will just confuse things.