All of your pro responses were about you feeling better. If you truly regret the liason just let it go and watch yourself in the future.
Focus on the relationship. Make amends with your girlfriend by being a better, more attentive boyfriend.
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Don't Listen to the Other Comment by: Take My Advice
The truth is always, always, ALWAYS better.
Why would you want to be in a relationship that is based on lies -- even if you think that you're doing it to make things better?
You don't have the right to make the choice for your SO of whether or not they'd stay with you. Always be truthful, and let them make that decision. Otherwise it is very unfair.
Six years is a long time. Unless you've been horrible to her in other ways, she will be able to find the other good in you (at best: stay with you, at worst: letting it weigh heavily on her mind before making the difficult decision to leave).
The obvious advice is DON'T CHEAT, but it's been done. So now, BE HONEST. It'll be hard but very much worth it for everyone involved.
The other comment is the most selfish advice. Anyone can look at that and see that it is not a healthy relationship.
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Don't tell her you cheated...thats my advice by: SL
I advise you not to tell her if u want to stay with her and try to work on your relationship and make her (and yourself) happy.
As long as you are sure she has no chance to hear it from anyone else, yes, this is my advice:
Don't tell her. I have cheated my bf as well. I dint tell him. Being a cheater it's not only my fault and of course not only his.
Cheating on him i realized my fault and I acted differently towards him, which made us come closer.
I cheated on him several times, every time when we had a big problem. I released myself in the arms of another man, but in the end my BF is the one i want to be with.
Take care and do whatever you think it's best for both of you. Good luck!