Dating a girl, questioning sexuality

I'm a straight guy, always have been and I've always even attracted to women. I'm currently in a relationship with a woman (a very attractive one at that) and I'm afraid of messing up what we have.However, I can't deny the fact that I have a serious obsession (for lack of a better word) with gay porn. I've sucked dick twice, once in high school and the second time a few months ago (before I started my current relationship). I enjoyed it immensely both times, but fear of being labeled as gay kept me from pursuing it any further. The second time I gave head, I also had anal sex - but as a top. I haven't tried it, but for a while I've wanted to try receiving anal sex. I didn't have the courage to attempt it at the time.Now that I'm with this girl, I want to give my relationship the best shot I can. We are sexually active together and I really enjoy it, and I wouldn't say that I long for gay sex when we're together.But when we aren't together and I'm alone with my thoughts, they wander and I find myself wanting a big hard cock inside me, whether my mouth or my ass. I'm insanely attracted to her in a way that wouldn't be possible if she were a man, so I don't think that I'm attracted to men like I am women. But I can't help wanting to be submissive and to be fucked.Is this just some sexual infatuation/obsession, or am I experiencing something that most gay men experience before finally accepting themselves and coming out? I understand things aren't black and white and I'm not trying to label my sexuality. I'm just confused and horny, and it's not a good mix. I hope someone can offer some advice here.