Hi Dana- From everything you've described Dana it sounds like your H truly intends to stay with his family. Will he consider counseling with you? And, have you checked with your dr. re. possible supplements for menopausal symptoms. At times like these when you feel completely overwhelmed it is definitely worthwhile to explore all sources of possible relief.
Try to muster up the strength that it sounds like you had during your roughest times with your H. Pull from deep inside and see all that you've endured and all that you've managed to accomplish in your marriage.
Although I know you feel weak right now, you really sound like a very strong woman who knows that these difficult times will pass. If you have not told him yet I would share with your H that you're not feeling that well physically and that you intend to see a doctor for it. My guess is that he will support you fully and that your focus on his infidelity will fade. In the interim though, I would also search on the board for how others have dealt with their spouse's infidelities. I remember seeing a book entitled "After The Affair" recommended on numerous times. Your counselor might be able to make other recommendations too.
Take a deep breath Dana and maintain a positive mental attitude. Best of luck--Jamie