It does sound like you are the only stable parent and your S. Is better spending the bigger chunk of time with you.
Initially you will find that you change your mind about what you want to do because of whatever emotions are guiding you at that time. That is why most places don't allow divorce until after a year. That gives both parties a chance to cool off and see how they really feel. I know when there has been adultery that time line can be shortened. I am legally seperated but not divorced. All our finances ect were taken care of immediately with the separation agreement. It is important to deal with that side of things including custody ASAP.
Keep moving forward and working towards being the person you want to be in life. Your wife will eventually either catch up or you will have moved too far beyond her and will create a new life. You never know what's around the next bend.
Me 52 H 44 T9 M 5 BD 12/11 H split 8/12 OW moved in 12/12 OW gone for good 6/14 We get closer again 9/14 SD 13 Me 4 Grown
Accept what is...let go of what was and have faith in what will be.
