blackhole soul,
There is good news and bad news
This is from personal experience.
The bad news is major depression often re-surfaces, sometimes for no apparent reason, sometimes because of more stressful events.
The good news, is there is help out there beyond counseling and meds. Both of those can be good, but meds especially ignore (in my opinion) the underlying problem.
Some talk-treatment makes it worse -- it is not good for a depressed person to go over their past over and over again. And it can help if you realize when you are thinking about the same things (past or present) over and over again, or thinking dis-heartening thoughts.
If you haven't already, spend some time here:
Learning Path
I realized I was depressed 7 years ago, and it has been up and down since then, but much more up than down. I'm glad to hear you are generally improved.
I'm not a professional; I hope to hear from some of the pros here.
~Mermaid