Infidelity Support Group
Any relationship in which one partner engages willfully in sexual relations with another outside of the partnership is considered to have experienced infidelity. This breach of trust is often traumatizing for the faithful partner as well as the relationship, and support is often needed to heal emotionally and to decide whether or not the relationship should continue after...
Go see a lawyer and find out what your rights are. Start secretly setting money aside.
You do not need to live with his mother. BTW, what does she think about her cheating son?
It will help you, too, to see a therapist who can help you work through these issues. Your H's cheating is not your fault. It is his choice. You have a wonderful life ahead of you without the pain this douche bag is causing you.
Good luck!