I'm going to tell my wife I will divorce her if she continues to try to raise our son as muslim
Does your son have a preference in his religion?
He said he loves her and I'm not ready for him to choose his mother over me. I'd do anything to keep him in my life.
It's understandable if you divorce over religious values but you should let your son decide on what he wants to be. If he's closer to his mother than it sounds like he wants to be Muslim which you should respect.
Marriage is a one sided thing. I'm going ahead with the divorce.
Marriage should not be one side.  Religious differences can be a difficult thing to overcome in a marriage.  Regardless, it would be best to teach the child about both religions and allow him to choose which one, if either he wants to believe in.