Is my husband gay?

I'm sure posts like this have popped up a million times in relationship forums, but since every situation is different I cannot find any information that settles my mind...so I thought I'd post my specific problem here and see if anyone can help.

I am 24 years old and my husband and I have been married for 3 years, together for 7. Sex in the beginning was awkward since it hurt for me but we still had a fairly healthy sexual relationship (we weren't doing it like rabbits, but we had sex about once a month). About a year after we started having sex, I found some gay porn websites on my computer. I didn't confront him but instead said something like "You should see these pics I found on my compy! They must have downloaded themselves! Too funny!" The pics mysteriously disappeared after that. When I found some gay group memberships in his inbox and asked him about it, he said he checked his e-mail at work and someone must have joined them as a joke. Years later I asked him if he still checked his e-mail at work and he had no idea what I was talking about.

Then, about 3 years ago (after being married) I found some gay pictures in the user cache of my system. Our sex life by this time had dropped off the map and we were lucky to get it on every 3 months. I was pissed and told him that if he was going to look at that c**p to clean it off my computer. He told me he wasn't gay and I told him I didn't care that he looked at it, but I wanted to know why. Until this day I have yet to receive an answer. During the same conversation I asked him why he didn't want to have sex with me. He gave some lame excuse along the lines of: "The sex the night of our wedding was so good that I didn't think I could live up to that." Ummm, I thought men wanted sex most of the time.

So I started being a little more sexually explorative and offered new and exciting positions, thinking this would respark our sex life and ensure that I could get laid a little more often. No worky. When I try to think of the last time we had sex, I want to say January but it may have been before Xmas. Not entirely sure.

I've been more and more tempted to have an affair (and almost did) although I know this is a totally not the right way of resolving the situation. I just want to be physically close to someone and right now that someone is not my husband. Even if he were to come home and say "You, me, bedroom, now" I would probably refuse him. And I know what you're thinking..."You should talk to him."...I try and try and try. Everytime I cry about it, I get sex and then that's it. Nothing changes longterm. So, really, there's no emotional payout for being open about the subject.

I used to blame myself. I used to think that it was because of the pain I expressed during intercourse and he was afraid to hurt me. Well, we stopped using latex condoms (the source of my ouchy) and sex was great after that. Then I blamed it on my birth control (Diane 35, known for extinguishing sexual wantingness) and switched. No worky. I even tried to blame my looks or personality or whatever, but (and I don't mean to toot my own horn) I have had guys express interest in me and even utter the line "If only you weren't married."

I am very very very confused. I love my husband to death and can't imagine life without him, but right now I feel like I'm living with a best friend or roommate. We hold hands and I get quick kisses, but there's no physical intimacy. I'd kiss my best friend the same way if she would let me.

Any meaningful advice at this point would be appreciated. I've spent my whole life trying to figure things out for myself and now I feel completely lost.