I [29M] found out that my fiance [28F] cheated on me about a year ago. I confronted her today. I'm devastated and don't want to give up 10 years of the relationship.

Few days ago one of our mutual girlfriends told me that she confessed to her about cheating. I don't know the context of the talk between them, but her friend decided that I should know.
We had a big fight around the period this apparently happened (she moved out then for about a month), but after the fight I decided that I cannot leave her and I love her to death, which I still stand by today. To my understanding she then evaluated our relationship and ended the deal with the 3rd guy. At that time I was suspicious so during the fight I asked about him, but she denied that anything ever happened. The cheating happened before the break.
So yea, something happened. She apparently had feelings for the guy, she was in an unhappy period in our relationship, it was a difficult time for her etc. It is irrelevant on what my suspicions were based, but apparently they were confirmed.
Today I told her I know. She denied. The talk was filled with emotions on both sides. In the end she didn't deny that it happened, just told me that it lasted about 3 weeks and was mainly emotional, she didnt confirm any physical interaction between them.
She begged me not to leave her and told me that I am the only one in the world that matters for her and that I am the only thing she has in it, no real friends and such, everything else doesn't matter. I suppose that from her point of view it was a year ago and we already had a great thing going again, because that big fight cleansed the deal (even tho it wasn't about the cheating).
I was preparing for today and it still hurt like a mother****er. I cannot focus on anything, I'm constantly thinking about our life that we built together. It was 10 years.
I helped her get part of her belongings and she moved out. I suggested a long break and didn't specifically tell her that this is the end.
Rational me knows it has to end. My heart is broken. But every other me can't even comprehend life without her. I just don't know what to do. I don't know if I'll ever find another person like her. She is my perfect match.
I don't want to talk with my friends about this partly because every time I think about it I tear up and I don't want them to see me in this state, partly that after 10 years of life together her friends and mine friends became the same people. I don't want them to take sides.
I took a few days off at work, but I'm just sitting here and thinking that I did the wrong thing.
Can I trust her? Should I give up the last 10 amazing years? I really love her guys. I can't stop thinking how she suffers right now. I can't stop worrying how will she sort her life from now on.
Moreso, I love her family like my own. Her little sister, well today she's 18 already, is like a sister-daughter to me.
How can I survive this? This is real bad, I just can't. And man, I'm already 29, how can I build a new relationship like this at that age?
I'm sorry, im rambling but im so emotional right now, the tears are running on my cheeks non-stop and the lump in my throat just forbids me to talk at all. Please help me.
TL;DR She cheated a year ago, I found out few days ago, she moved out, we both cried, she begged me not to leave her. I don't know if I did the right thing.


Source.

Relationships are about forgiveness. Time to man up, talk it out, and forgive her. If it's true love you'll get past this. It doesn't seem to be a reoccuring issue, so discuss it and move on.

Once a cheater always a cheater, selfish behavior. Kick her ass to the curb you deserve better. And sounds like she wants her cake and eat it too. Something brought up the previous fight, her mostly likely cheating and sleeping around and using you bro and wanting to "love" you at the same time, how can you do that to someone who supposedly trusted you. End it, don't waste your time people like this will never change and can never be trusted. She most likely was playing you from the very start

^^^^take his advice and be a 40 year old virgin in your mama's basement that never learns to love, communicate, or forgive the human race is always an option too.

Nice try Christine but i live in the city now and have connections and have my friends back from NYC. And i took care of that other part of business while i was in Florida but i guess you would of figured that out by now. You know what *they* say about assumptions and you just did it lmfao

Seriously? Is that impossible?

What was his name?