I think they call it Homophobia. This is a term typically used by openly gay men (and women) to describe people who dare speak out against homosexuality. The implication is that such objections come from a suppressed homosexuality that the person is afraid of (phobia).
In my opinion there is a kernel of truth to this falsehood. I am a lust addict. There was a time that I took a vow (not recommended) to not look at untznius images of women on the internet. Guess what happened? After a while, my cravings for porn were so strong that I actually thought about looking for untznius images of men to get my fix. I didn't do it for two reasons. First, it wasn't in the spirit of what I was trying to accomplish. But there was another reason. I knew that, although I am 99% straight, if I were to start looking at that stuff, I would get hooked. Lust is lust. And I certainly didn't want to go there.
The potential is in all of us. That's why the Torah warns us against it.
So my friend, don't get too paranoid or concerned. When you're messing with lust, anything can happen. You're not gay. You are afraid of being gay, but that isn't a problem unless you make it one.
Be very sober. Practice aggressive shmiras eynayim. Guard your mind against all lustful thoughts. Think about giving up the forbidden physical contact with your girlfriend (talk it over with her). Daven for sobriety and clarity. You'll be fine.
Have a great clean day!
Alex