This is a long deep rooted problem that extends far back with your own personal/physical/psychological problems that created an environment that could have netted you a few asswhoopins if she had a mind to find someone willing to do it for her. Appearantly you hurt her to the core too many times. That will cause her to seek sympathetic and supportive help. So she appearantly sought this from an old friend. Left alone in such a situation long enough and the two friends can become more than friends. Does this have to be some well thought out premeditated intent to cheat? Hell no. You admit yourself that you created this atmosphere in your own relationship. You have since sought help, and believe you are on the road to recovery. The thing you must do now is convince your spouse of this, and win back the trust and love she once had for you. This may be an impossible task.
I would advise that you present the best of you, and do your best to win back what you lost, and get serious counseling. If it doesnt work out, then its probably best for both of you. Recovering trust is one of the most difficult things in a relationship. Once that trust is lost, it can be nearly impossible to regain. She feels you betrayed her, and you feel she betrayed you. Now you both have to work on rebuilding what you have collectively lost. If its not worth it to either party then no amount of violence or influence will make a difference.
No matter what happens, you need to be there for your child. Dont create an atmosphere where your child fears your presence or hates you because of the hate you harbor for his/her mother. Life doesnt always work out as we plan, but we must adjust to what life presents us with as reality.
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