<human>: Summarize the given text in a few sentences.

Apologies upfront if this is too long.

My girlfriend and I are in our 30s, and moved in with each other 2 and a half years ago, after moving across the country to live in a bigger city with better job prospects for her.

Right from the onset, things went wrong. Her dad was diagnosed with depression, and we ended up falling pregnant and no going through with it. She went onto birth control, and the sex dropped off to being nearly non-existent. We had been fairly distant since then, but started to mend our relationship probably around 6 months ago.

So, everything (except for the sex) had been going pretty well.

Then last Friday, she goes out drinking with a girlfriend of hers, and when I am unable to pick her up (also had been drinking) she tells me she'll just go back to her girlfriends place to crash. Except, 45 minutes later she turns up at the front door, crying her eyes and tells me she cheated with this girl. She got fucked by this other girl, and didn't say no. I believe her when she says she just froze up and let it happen until she faked a finish so it would end. I believe her because she hasn't stopped crying since it happened.

I have been trying to feel angry, feel something, but I've just thrown up a wall and can't feel anything. I think I want to get through it, but I just don't know how to start. And I don't feel like I have anyone to talk to about it.
<bot>: gf cheated on me with a girl; she appears truly remorseful; I think I want to make things work, but I can't feel anything, and don't know how to start