My girlfriend slept with someone else in a week break

Around Christmas time last year my relationship with my girlfriend of 3 and a half years started to seem under strain. We had always been very close and spent practically all of our spare time together. She has always been quite a shy person, finding social situations & making new friends a bit hard.

Late 2007 she started a new job working for a large company of a kind she was not used to being in, I was warned by others that it was quite an institutionalised type of setup and the workers there tend to form close-knit groups. I never thought this would be a problem.

Anyway, as the year went on, my girlfriend was making friends with her peers and getting invited to more social situations with her colleagues.

This wouldn't have bothered me as such apart from sometimes she would go out with them at weekends without telling me and without answering her phone when I called.

When it came to Christmas this became even worse, she wouldn't tell me what plans she had unless I specifically asked. When I asked if I could come to one of the gatherings (they were all generally young people just going out for a drink for a leaving do - the second leaving do for the same person as the week before) she basically started the "I don't think this is working" routine. Although we didn't split up at that time and she regretted saying it, it still hurt a lot that what seemed like such a strong, long running relationship could be so easily suggested as not worth it over such an unimportant matter.

This affected me quite a lot at the time - it never crossed my mind that our relationship could end like that. I've always suffered from mild general anxiety but this took it to another level, I was losing a lot of sleep over it and it was affecting my job. I went to a doctor to sort out my anxiety issues and she put me on some anti-depressants for it. I've never wanted to take ADs but my girlfriend (who ironically was working for the company who designed them) told me I should.

When taking the ADs my anxiety got worse and I started feeling depressed, an emotion that's never really affected me before. The drugs warn that this will probably happen the first month or so though, so I persevered.

Though I've always enjoyed a drink, through this period I started to drink heavily and one day when I was drunk me and my girlfriend got into a huge row and she dumped me.

When I sobered up I was heartbroken and begged her to forgive me. She wouldn't even talk to me.

For a week I kept sending her emails and messages - some apologetic, some angry, but all "in the name of love". She came and met me twice, always standing her ground that it was over (even though I didn't believe it). The second time though we did sleep together - a break up shag.

The Friday (we split up the previous Saturday) she sent me a message saying she was going to write an email explaining exactly how she felt, but that she was going out so it would have to wait.

That same night she sent another message that just said "I can't live without you". I thought Thank God she's come to her senses.

I rang her straight away and she said - crying - that she had to tell me something. I asked her what and she said I could probably guess. I said "you've slept with someone" and she confirmed it. When I asked her who, she told me that it was one of her workmates and not only that but the one that I had had a problem with because I thought he fancied her.

Maybe it was the ADs I was on but I decided that no matter what I love her and so I had to forgive her. So that's what I said and I took her back, even though I was extremely hurt.

I continued with taking the ADs which continued to have a more and more profound effect on my frame of mind. I started to not care about anything and I felt hard done by my girlfriend. This manifested itself in me drinking more and more heavily, taking cocaine at an ever increasing level and flirting with any girl I came into contact with. I felt that I had a free ticket to cheat on my girlfriend and she couldn't say anything.

This sort of self-destructive behaviour went on for around 4 months in which time I went into hospital on 5 separate occasions for 3 different reasons and got arrested twice. I also got into massive debt from all the drug abuse and took a stupid amount of time off work and university feeling sorry for myself. (Btw, this is uncharacteristic of me, straight A student, never arrested before).

It all came to a head at the end of April, after having punched my stepdad and being kicked out of home by my Mum. I stopped taking the pills that night.

3 months on now and I have returned to my normal state of mind. I'm not taking drugs anymore or flirting with other girls and I'm feeling a lot more healthy. But I still can't get over the fact that my girlfriend slept with another guy within one week of breaking it off with me.

She is the only person I've ever slept with, I was her 12th and now she has a 13th.

I know she didn't technically do anything wrong so I suppose my hang-ups are more jealousy than anger. I just don't know if I will ever get over it or whether it will keep popping up for years to come. It wouldn't be fair on either of us that way.

The reason I'm posting on this forum is to see what other people think, was she wrong, am I a mug, if they have had similar experiences and how is it best to get over it.

At the moment - now that I'm sane again I'm unsure whether I should or want to commit any more to this girl.

Sorry this post was so long, I look forward to hearing what people have to offer.