It may take your wife a while to believe you love her. I asked my husband to stop saying it to me because I could not stop myself from thinking every time he said it "that's a lie cause you wouldn't have messed around on me with so many people if you did".
I now believe my husband loves me to the best of his ability and he appears to be doing everything he can to learn how to interact in the world in a healthy way primarily through therapy.
It will be painful for both of you for different reasons. Addressing your CSA will be your primary battle and repairing your marriage a secondary battle, for her it will probably be recovering from the devestation of the infidelity and then learning how to navigate the CSA.
It is unbelievably indescribably painful to be betrayed by a spouse, but the sister thing adds a complicating factor because now two people who should have been protective of her heart weren't.
If you want to try to keep the marriAge intact, keep working on healing. Sobriety, therapy, accountability and as much transparency as you can muster will help. She'll be wary, hesitant and suspicious (and she should be). You must be patient and understanding even while you are dealing with your own issues.
If you think your wife would be interested I've got a whole list of books to read (and some to avoid!). Just let me know.
Wife of a survivor