So? You start exercising. Alone. Two things happen here:
The endorphins help to stop the hamsters running on the wheel in your head
You begin to look really REALLY good.
I say sign up for your local gym. Take a class once a week in something you have always wanted to do. Let H know you will be away that evening. Ask if he would like to watch his son or do you need to get a sitter? Do your son's special needs allow for a garden variety sitter or do you need respite?
Either way, it's time to make a little time for you