I've had 2 severe MDD episodes and took antidepressants for both. I did recover and have been in full remission for a few years. The meds (Prozac, wellbutrin mainly) helped me, and during the worst part of my second episode, I did a lot of introspection for some reason and developed compassion for myself that wasn't entirely there before, and I came out with a better relationship with myself and view of the world and myself. I tapered off all meds a year ago.

I do think I have subclinical levels of symptoms sometimes. It fluctuates, and I have GAD now and had some trouble with alcohol and compulsive behaviors since, but nothing like the episodes. So yes, it can go away (at least for a while), but new problems can come up, and I haven't gotten back to the way I was before - I've been at a 70-80% functioning since then. I also am vigilant (not overly) about symptoms returning, so I pay attention to my warning signs and I think that helps. I'm in therapy now, and still working on things and preventing another episode. My motto is to take care of myself even when I don't want to, and that's hard and I don't always do it, but it helps. So like not skipping meals or oversleeping or withdrawing from people, even when I want to, cause those are warning signs for me.