okay, I will try this again. I lost my last response to you. It is better to learn after 9 years than after 33 years that the two of you can not live together.
I am not sure if you will not have contact living under the same roof or you will not have intimate contact. It may be for the good if you do not have intimate contact for your own personal protection.
Allow her to sort things out. She may come around, if not allow her to leave. You can love her from a distance and at the same time permit yourself to find someone else when you heal from the pain.
Your son will be better off if he is not living around arguments and tension in the home. if you split, he will be hurt and not understand the reason mom and dad can't live in the same house. One important thing you may want to ask your wife and yourself...don't divorce the child. Allow him to have two parents in his life. That is if things come to a place that calls for divorce.
I hope things work out for the good of the family.