Hi mickyjupiter
Welcome, and it's great that you found this site. The understanding and support that you're giving your husband is wonderful, as is the fact that you are educating yourself about his illness.
The blunt truth is that you can't stop his vicious cycle -- only he can. He has to want to get better, otherwise you'll end up either losing yourself in his depression or leaving because you can't take any more. You are definitely not being selfish to want to have your needs met as well as his -- I think that is one of the characteristics of a healthy relationship :)
Would he work on this program? It may be easier for him to do, if he's uncomfortable with working with a therapist. There's also a questionnaire here which can form a basis for a discussion with his GP.
As for the medications, if his GP knows about [u]all[/u] the meds your husband is on, you'd hope that it's okay, though I certainly understand your concern. These are serious drugs and they need to be taken exactly as prescribed. I'll admit that I also let my prescription run out when I was deep in the depths -- once, and I showed up at my late-night pharmacy with some excuse for them to give me some to tide me over until doctor's hours. It happens, but it's not a good thing, because going on and off creates havoc with the brain chemicals. The upside is that you are now aware that he may need reminding to refill.
My opinion: that you're the cause of his depression was probably just him lashing out in anger. He really does need to take responsibility for getting over his depression, though. Hopefully he'll be able to find help from this site.