Can I forgive and forget and taker her back?

I want to apologise straight off the bat, this is going to be a long post. Please stick with it as I want to get everything down so you know the whole story.

Ok I’ll start by telling you about my relationship. I've been with my girlfriend for about 3 and a half years. I've known her for about 8 years and we have always had a little something for each other even before we actually got together. The relationship has always been perfect; we've never had any major arguments throughout the duration, we spent pretty much every night together and we've always been honest with each other. Trust has never once been an issue for either of us. My girlfriend has always had self-confidence issues and it has taken almost all of the 3 and a half years for me to build up her self-esteem. She has only just recently become confident enough to be around me naked. Her previous boyfriend of 2 years can only be described as a monster and constantly told her that she was disgusting and was forever putting her down.
Anyway, we have always talked about the future, getting married, our own place, having kids. The whole thing. However, there was one thing that got in the way; University. We talked before she went but probably not as much as we should have. With my job being on a rota’d shift, my days off are never the same and I have to work 3 weekends a month. We agreed before she went that I would see her once a month, on my weekend off. We left it at that.
Anyway, she went off to University about a month ago and this is when everything went downhill. Once she was away she was obviously out meeting new people and living independently. She was having a great few weeks of fresher’s. The difficulty of being so far apart and spending less time together than we were previously used to was becoming apparent for me. I was struggling, being left at home, while she was barely having to think about me due to being so busy with going out, getting to know her flat mates and meeting new people. I told her I wanted to make it work and even came up with ideas such as sending her my rota and driving up to see her on the days I had off work. She wasn't sure about what she wanted, I assume because Uni felt like a better life and she was enjoying it more than being at home.
One day, I went to use Facebook on my laptop (which she used to use more than I did since I got a new computer) for the first time since before she had gone. I opened the home page to see I had a message. I clicked to read them and it was from a girl I didn't know. It wasn't logged on to my account. My girlfriend had obviously left herself logged in and forgot to log out and no one had used it since that time. The messages were pretty apparent. It started with her friend asking her if she ‘had “banged” last night’, to which my girlfriend replied she had. During the conversation my girlfriend said she could ‘do with another session tonight’ and that ‘he is so sweet’. She also mentioned that she didn't take her bra off (which would make sense as she has issues with people seeing her boobs). Obviously alarm bells rang in my head so I questioned her on it, apologising first that I had read her messages. She assured me it was just ‘banter’ between her flat mates and she explained what each part of the conversation meant. I didn't think it added up but she was giving me her word and there had never been an issue with trust, so I let it go.
I went up to visit and brought it up again and she once again assured me it was just a joke between her friend and I had nothing to worry about.
A week or so later, she came home for a day and we decided to talk about what we wanted with our relationship. We both said what we had to say and she finally came to the decision to split up because she felt it couldn't work. I accepted this despite it not being the decision I wanted and I stayed over and we went to bed. I woke up during the night and checked her phone to see if there were any texts. The first text I found was to one of her flat mates. She was saying that she had left the club with a guy I will call TG. Her friend replied with something along the lines of ‘oh yeah? Fill me in tomorrow ;)’. The next text was from another flat mate. She asked my girlfriend where she was to which she replied ‘in a taxi with TG trying to get sex’. Her friend was encouraging her to do it, telling her to ‘take him home and **** him hard’. She replied with ‘I would but he doesn't want to. ****ing great!’.
My suspicions were becoming apparent. I checked to see if she had any texts from TG. I saw there was. She was texting him things like ‘you up for another night? I know you want to ;)’, but by this time, it was obvious he had got what he had wanted from her and was giving her the shoulder, making up excuses not to meet up. I was crushed. I got up and got dressed in an attempt to sneak out but she woke up and asked me where I was going. I asked her who TG was, to which she broke down in tears and admitted to sleeping with him twice.
Since finding out, we have talked about it on a few occasions and she is constantly telling me how sorry she is. She says she hates herself for what she has done, wishes she never did it and she says she doesn't know who she was at that time. She has told me she considered committing suicide due to feeling so guilty. She wants me back and has offered to give up Uni to come home and be with me (which I obviously couldn't make her do). She has also offered to give me the password to all her accounts like Facebook and email, as well as telling me I can check her phone whenever I want to. She says she wants to make it work and has realised how much she has taken me for granted. She says she will wait for me for as long as I need, so as I can come to terms with what she did and doesn't want anyone else but me. I still want to be with her, and I want to forgive her but I am confused and scared about whether any decision I make will be the right one. She has begged me, day in and day out to forgive her and take her back since the day I found out. I have talked about it with a few close people but the problem with that is they are my friends and are obviously going to look out for me and take my side. I really need some neutral advice from people who don’t know either of us and won’t take sides, putting themselves in both our shoes and giving advice accordingly.

Sorry for the really long post and I really appreciate anyone that has taken the time to read this and given advice.

She has been unfaithful. I would not tolerate this but only you can decide. What makes it worse is that she only admitted to it when you found out - she was not exactly full of remorse was she. And the stuff about suicide is just so much bullshit. She has checked out of the relationship. I suggest you do the same.

The other guy gives her the cold shoulder, she comes running back to you...

Entirely up to you, personally i couldn't take back someone who had cheated, the trust is gone and they'll always be that bitterness over what happened which will just rot the relationship anyway.

Depends though, can YOU totally forgive her and move on without it bothering you?

Thank you both for the replies.
My first thought originally was to just break it off and cut all ties with her, but my heart seems to keep telling me it would be a drastic mistake.
I've thought of suggesting a temporary break from each other, avoiding all contact for a month or so to see how I feel about the situation after that hiatus.
What length of time would you suggest if I were to take that form of action? Or would you suggest not to do that at all?
As for whether I can totally forgive her and move on without it bothering me, I'm not sure yet as it's not long happened.
Our love is really strong and it would seem such a shame to let go of something special that I have invested my entire person into for the last 3 and a half years.
Would I look back in a year or so thinking 'what if?' and totally hate myself for throwing it all away?
I would like to think if I took that course and regretted it, she would still be waiting for me like she said she would, but can she really wait for 3 years without so much as wanting another guy?
I love her so much but I hate her for what she did.
Is it all just a case of waiting it out to see which outweighs the other and acting accordingly?

Be true with yourself. She changed. She's not the shy girl of yours anymore. She's been with you for a long time. And her environment changed. She found out that there were many interesting guys out there. She had many oppoturnities to have fun. And sometimes she forgot you. But the cold shoulder of TG kicked her back to reality. You're the only one who loves her at this time. You're the only choice of hers. She will stick with you until she gets a new man. It's not your choice anymore. It's her choice, actually.

Wow, your "perfect" relationship went off the rails just one month after she went off to school. Maybe it was never as perfect as you imagined.

It's sometimes possible to forgive someone for cheating and get the relationship back on track, but this doesn't seem like the right circumstances. She still has years on campus ahead of her, and she is young and curious about other guys. The chances are really high that she's going to cheat on you again. Even if she doesn't, the uncertainty is going to eat away at you. You are going to be better off moving on and meeting somebody new.