Is he waiting for me to leave my boyfriend? Confused..?

It sounds like he is interested in you, but realizes that you have a boyfriend (that you talk about to him) and won't interfere with that. I don't think he is trying to play you at all. When he flirts with other girls at the office it's probably just because he's single and has no obligations to anyone. He does it in front of you because he probably thinks that it doesn't matter to you since you have a boyfriend. So you have a few options: dump your current boyfriend that you seem to be getting tired of and try to go on a date with this guy, or keep talking about your boyfriend to you co-worker to make the message clear that you aren't/won't be interested anytime soon. Hope this helps!