If you are not at the point of wanting to divorce than I would suggest getting a legal separation (so you are not accused of abandonment), separating bank and credit card accounts, and then moving into another apartment. At least this way you will be able to emotionally detach and not care what she is doing and with whom. It will help retain your sanity and not make you feel even more like wimp. During that time you could focus on improving yourself emotionally and spiritually. Once you reach the point where you feel more confident and stronger emotionally the solution as to what to do with your marriage will become more obvious.
