Yea ketamine is definitely the next big thing. I've heard many good things about it and it seems really promising.
I think from the insurance companies perspective why cover new expensive treatments when there are far more cheaper options on the market? Unfortunately, for consumers this ultimately leaves us with less options, especially when the so called established medicines don't work. This leaves us out of most of the cutting edge medicine being developed as we are always stuck on older more established alternatives.
Oh I just remembered an alternative treatment I heard about a while back... It's called Transcranial Magnetic Stimulation or TMS. It's supposed to activate nerve cells in the brain to improve symptoms of depression. Look it up if you're interested.
Unfortunately, as with the ketamine, I have a feeling insurance companies won't cover and it probably isn't cheap!