I'll give some more background, probably more than I'm comfortable with but I'd like some more opinions from you guys because I've really been dwelling on this a lot lately and I can't really share this with anyone else in my life. We have been together for 4 years like HJ said (I dunno how he knew that offhand, but anyways...). Things have been very different since September though. We met at Univ. of Michigan and we were both living in Metro Detroit relatively close for 3 years (2005-2008). Since September (08) she moved to NYC for her Masters, and since January (09) I moved to Maryland for mine. We have been going back and forth every few weeks and visiting each other. We've never lived together, and we've always had a good bit of distance and allowed each other a great deal more personal space than I think most couples have with one another. There's a lot of freedom and a lot of trust, I've always liked that and I'm pretty sure she has as well.
We almost broke up last November, and we had talked about splitting up then just because there were a lot of things going against the relationship. I applied for the Navy Officer Corps last summer and in September I was still under the impression that I would be going into the Navy as an intelligence officer -- we had both agreed in September that because of the circumstances (her in NYC, me being on a boat in the sea somewhere) -- that we would have to have an open relationship from that point for awhile, because of the small likelihood that we would see each other for any extended period of time if I was locked up overseas on a pair of 18 month tours and she was in New York. I subsequently got denied entry into the Navy in October because my medical waiver did not pass the medical board, and then I got accepted to Univ. of Maryland in November (which I had applied to basically on a whim/backup earlier in the summer). So fast forward to Thanksgiving, I visited her that weekend to celebrate my getting into school and to have a good holiday with her and her friends and we just had a huge fight all weekend. In the 2 months where she started school, I prepped for the military, I got denied to the military, I got into grad school, I prepped for grad school, etc. etc. we both made huge changes to our lives -- and in that time, in NYC, she told me that she had sex with two other guys. I know this is a red flag, and a lot of you will say right away 'fuck her, you're an idiot and you deserve this' but there is a pretty substantial gray area which completely clouds my judgment on this issue. We had both agreed that it was okay to see other people in this time (given the circumstances, which we agreed, but which then changed to neither of our expectatations). But only she took advantage of this, and when we fought about our relationship all weekend on Thanksgiving (and the majority of it was all about other stuff completely unrelated to the extra-relationship sex), we both agreed to continue the relationship but at that point it was barely holding on. In the back of my mind I don't think I've ever fully regained my ability to trust her 100% of the time, which is why this sex hangup, which should be a minor thing (maybe we just need to spice it up in the bedroom, etc.) is turning into a big deal in my mind.
Despite all this shit in November, things went pretty well throughout my first term here at Maryland. We got together several times in the Winter and Spring and had a lot of fun, went out, just like old times. Since about March though, it just seems like she's been a lot less responsive, like I had pointed out in the initial. Like I said we get together about every 2-3 weeks, so we've probably gotten together 4 times since mid-March. And like I said, we've been doing the weekend dating thing for years, and in the past, we would hit it until my dick was literally sore by the time I left, now it's completely different. In April I brought her down and took her to my University Formal Dance. I bought a suit and tie and shoes etc, took her out to dinner, rolled out a $100 bar tab at the dance, probably one of the nicest times I've ever shown her, and expensive as fuck on my end. I thought it was all good and took her home expecting some wild prom night action and she basically just passed out and left me out in the cold. Since then it just seems like several times, we go out we have fun, we get home, nothing. I buy virtually everything when we go out, and help her out all the time, and I feel like I'm just kind of fading into the background, not just from the sex but in her overall investment in me in all ways is just becoming lacking. With the sex, I get in bed with her, curl up to her, get playful etc. -- nothing. I just feel like I'm not doing it for her anymore, and that's a big hangup for me. If I want to blow a load I can do that myself in 60 seconds and it feels great. I like sex for the reciprocity of it, it's always about the lady. I like to know that I'm making her feel good, and when I'm having sex, if she's not having a good time then I'm not even sure what I'm doing there, I might as well be slamming my dick in a refrigerator door.
Anyways that's basically the whole story. The long version of my doubts. Give me some advice.