Ok, so here is the story. In March I went on a study abroad trip to Japan, leaving my gf who I'd been dating back for over two years and we were even living together before I left at my home college. Are communication was severally limited, I eventually got Skype to call to the US, and we talked on AIM, but we still were drifting apart but were still dedicated to each other. Towards a month into the program, she suggests to me an open relationship for my sakes, she was very against it but didn't want to limit me, knowing how much I wanted to be with an Asian girl and knowing how far apart she was going to be. I would never had agreed to it if it hadn't been for the summer before where she was at school for summer and I was back home, and she had ended up drinking with this one guy we knew and he drunkenly got her to have sex with him, we lost our virginity to each other and until that point had only been with each other and we both cherished that. Also at first she told me she couldn't go through being with anyone else, she couldn't do that to me. So I decide to go for it, I thought it would be a good experience for me in particular so I wouldn't feel I was missing out on anything only being with her. Time goes by, and I'm not all too serious about having sex, but she finds comfort with this one new friend who she met through another one of our friends. Things happen and they end up having sex. When she tells me this, I can't help to feel devastated, I know we mutually agreed but I was always truly against her with someone else. They have become friends with benefits and meet up now once a week to have sex.
All the meanwhile it is hurting me more and more, and on top of that I haven't found anyone of my own, and I only have a month left in Japan. I'm feeling incredibly lonely while this is happening causing an assortment of mixed emotions just getting to the point where my stomach hurts and me breakdown recently. I feel inadequate not being able to find anyone, and I feel if I go back empty handed when she had the advantage of something originally meant to help me I won't be able to let it go. I am way uncomfortable with the act of her doing it, I don't want to have someone else connect with her in that way and do those things, I feel they are a special bond and it sickens me thinking someone else has done something like that to her, plus the whole act grosses me out. I've tried to talk to her, but it doesn't help much. She assures me I am the one she truly loves, she holds no emotions for this other guy, that "he is just a breathing dildo," and that I'm the one she wants to be with for good, and that she's not into it with him, and only participates with me, and she tries to imagine me there instead, and that it means nothing to her. Problem is it means something to me. That I'm the one she cooks good dinners for, helps out with various things, and does a lot of other things for, and that shows she truly only really. The problem with me isn't that I doubt her love, just the whole situation doesn't sit well with me, and I feel she doesn't understand my feelings. I've tried to tell her how I feel and that it is really hurting me, but she feels after already having done it that more times isn't going to hurt things more and stopping won't help, but it does hurt every time I know they do it. I can't talk about it with her because she doesn't know how to make me feel better. She doesn't want to stop because she was depressed before without me, and this is the only thing that is making her slightly feel good and she enjoys it but not as much as with me, but I feel if she really loves me, she would stop this if it is making me uncomfortable, and she would give something like this up for me.
I don't know how to feel or react to this now, I feel very empty inside and I feel I have no one to truly talk to about this. I realize this was a big mistake, that I never wanted her to be with anyone else, and that I don't even truly want to be with anyone else, but it took me too long to figure that out. I came very close to breaking up with her this morning, but at the last moment decided not to, because I do love her, and I would be more devastated without her, and I can't have that on my head with the end of my semester coming and a bunch of final projects and final test coming up soon. We agreed from the start that this would end as soon as I got back, but it is really bugging me now, but I promised her I would find my own happiness, but it is still bugging me and depressing me a bit, and I feel I need to talk to someone about this...