Jonpen-
Let me begin by saying I'm sorry to hear this, I have been there and I have seen God do miracles.
Two things come to mind:
First understand that love is not just a feeling. There probably is a deeper root to what your wife is saying. If you get the opportunity to meet with a man you respect, share with them your story, from the beginning when you were first dating and be very open and honest. Pray that God would give you discernment on the actions of your past and how He CAN change you.
Second, I will encourage you to take the high road. Interesting thing about God's love...it's not deserving or earned it's not because of anything we've done. Avoid costly blowups, and do your best to be an imitator of Christ. Don't be prideful, but rather be faithful. Choose to do the right thing because it's the right thing to do and in obedience to Christ. You can't change the past, but you can be forgiven, therefore press on toward the Goal which Christ has put before you. First your relationship with him, second your relationship with your wife, and then your children.
In 1 Peter God shares "that by doing right we may silence the ignorant talk of foolish men"
Take charge of your life and responsibility of your actions. God doesn't call you to be a good husband because of your wife, but all the more because of what Christ has done for us! So when you think there is no way you can press on, or that she is giving up, rest on the hope that God is faithful, even when we are not.
God bless you dear brother.
My thoughts and prayers are with you.