So to summarise:
1) You have a boyfriend who you will not under any circumstances give up.
2) You fancy a straight man, who probably doesn't fancy you at all (by default).
3) This man is your boss, at your place of work.
My good man, if ever there was a set of circumstances that lent themselves to a non-starting, calamitous and impossible relationship, these are them.
You know the answer. You just gotta accept it and move on.