I think your notes contained the following information; please tell me if I'm wrong:
He cheated when you were working 70 hrs a week and
he has an illness that reduces (at least) your ability to have sex with him and
you have (reasonable) scruples about cheating on him and
he is unwilling to participate in those physically sexual activities he could with you and
he has online relationships with sexual content and
he wont _*let you masturbate*_?
The behavior you describe sounds abusive to me. Sounds like you have a bdsm relationship where he has all the power and (despite his illness) sexual outlet while you have the limitations but not the features you'd like. Your interest in bdsm is the least of the problems you mentioned.
At the risk of sounding like Dear Abby, have you thought about counseling? With him if possible, but (having been there myself - with my wife) you might want someone to talk to in real life. Find someone who does relationship / marriage / couples counseling and tell your tale. A professional wont be shocked and might be able to help.
You have my very best wishes.