Drifted apart whilst at University

[breakdownbill]

Hi I'm a M 33 and W 31 been married nearly 9 years and together for 12 2 kids D 8 S 6.
Sitch - been having intimacy problems and neither of us communicating properly for the last 2 years. This has coincided with me going back to UNI and spending lots of time studying. In order for it to work my wife had to work full time in the day & I had to work part time in the evening - so very little time for the relationship. My wife took up ballroom dancing about 2 years ago & since she has acquired a new circle of friends and a dance partner. She loved it so much she convinced me to start dancing last September. This was great as we spent time together once a week every week and had fun - it was our night. This soon stopped and my wife said she was frustrated dancing at a beginers level when she was more advanced, so I decided to keep it going so I could be as good or good enough for her to dance with me & went alone.
Around Christmas I noticed my wife was non stop texting all the time & said she was messaging her friends. At first I accepted this but noticed that her phone was never out of her hand, ever!! Then the nights out on a Saturday started with her dance friends coming in @ 5am and being hung over all day Sunday. Whilst I was looking after the kids - doing the housework & trying to study.
Then in February we were going out dancing & my wife wanted to go out to town afterwards - I said that I didn't want to because we didn't like the same places and that I was tired (I really meant I didn't want Wife to be hungover so I couldn't study). This really hurt my W as she thought I didn't want to be with her. I instantly realised what I had done & tried to apologise & said that I would love to go out anywhere and that I was an idiot for saying no - My W said it was last straw and that she thought our marraige was over and that she can't do this anymore. This came as a real shock to me & it was the Bomb!
It made me start to reflect on our relationship and how I'd been taking my stress out on others and not enjoying myself with W and kids (D 8 S 6). I then started to do everything possible to make it up to her which you guys call smothering - didn't work - she didn't believe anything I said.
Then a couple of weeks ago she went out looking like a million dollars with her dance friends and I said I'd wait up for her, she came home at 8am and I had been worried sick all night. She said she'd fell asleep at a party, but I knew she was lying. So I said I was going to move into my sisters and give her space & still take the kids to and from school. After a night apart she said she wanted me to sleep on our couch, which I thought was a start. I just kept getting knocked down every time I made an effort & my UNI work has suffered, when this week she asked me out of politeness to go out with her friends, I said yes & drove there, so I could leave if it wasn't pleasant. I made a real effort and she shunned all my dance moves and affection & at the bar she unzipped her top & flaunted her bra in front of me - sort of saying here's what you're missing. I was disgusted with her & left the club & went home.
The next morning I said I didn't want this anymore & couldn't undestand why she had been so cold over a row & that I was going to tell the kids that because she didn't love me there daddy has got to move out. She looked crushed, so I left the house for a few hours and picked up the kids to take them to my sisters to play. When I came back I started to pack a bag and she came upstairs and asked me why I was going & I said after last night I know that there is nothing there for you in your cold heart & that I am going, because she didn't want to fight for our marraige. I told her that all's I wanted to do was be with her & make her feel beautiful & make love to her. She started crying & said she thought I didn't love her & that she thought I was having an affair because I was in the library all of the time.
We kissed and made up which was amazing and had the best sex ever!! Then later on she said that she hadn't been totally honest with me & that she had got close to her dance partner & that he was texting her all the time & that she kissed him on a christmas night out & that the night she came home at 8am she was with him - but they never slept together. I don't know whether to believe that part or not, but I was so happy that I knew she still loved me, That I forgave her and took her back to bed and made love twice - it felt better than when we were first together.
She deleted his number & said that she will delete any messages he sends and not reply to them & that she will stop dancing so she has no contact with him. I want this to work so bad, I have forgiven her but I have got some trust issues & the thought of another man touching my wife makes me feel sick.

Do you think I am right to forgive my wife so easily? I just love her so much I would do anything to make her happy.
Apologies for the long post, have you got any advice for me?