Another bromance?

I was out recently with a girlfriend for Halloween. One of her male coworkers showed up with a male friend, and she asked them how they knew one another. The friend of the coworker responded, without much hesitation, with what sadly seems to be the standard response of putting his arm around the coworker and making some comment to the effect of them being more than friends. I had been talking to the coworker and having a great conversation before that. But, I instinctively gave the friend an awkward and uncomfortable look that was so obvious he quickly removed him arm from his friend and said "Not really!" (as in we are not really a gay couple). The guy I had been talking to fell silent and didn't acknowledge his seemingly gay friend's moves, but the conversation quickly died then and there. I would say it's actually the most common response I get when asking two guys how they know one another! I found myself hoping the one I had been talking to wasn't gay since he didn't engage in his friend's "game," but any magic was immediately squashed! Not to mention I felt I was initially falling into the trap of trying to rationalize reasons he was straight when I wasn't sure if we would keep talking. In the end, I came home being happy that my gaydar saved me from blaming myself for him not getting my number! ~Heather R.