I loved the fact that he was bisexual but not a televisual bisexual-who-sleeps-around stereotype. Now we find out that he seems to view himself as hetero, it's just that Jack's that awesome.

I'm choosing to believe he's just as you say but he's not out even to himself yet so for now he's using the ''it's just this guy' excuse. He's clearly coming to terms with it himself at this point.