If I were you, before I would do anything, I would first go to therapy and work with a therapist. That or pick up a good CBT book.

To me, it sounds like you have a lot of questions to resolve first. I would do that before you change anything. For example why do you think you are doing a minimal amount of work and does that actually mesh with reality? How do you define and measure work output anyway?

You mention dealing with depression for example. In my experience dealing with depression itself is a full time job. That you held down a second job during that experience is a major accomplishment. Go easy on yourself.

Remember above all that your thoughts create your emotions. Ask yourself why do you feel that way. What thoughts underlie the feelings. Question those thoughts.

If you are in Mountain View or the bay area, I'd recommend going to the Feeling Good Institute. I'd also recommend reading Dr. David Burns book Feeling Good.

Consider CBT as a set of tools for your brain and human operating system. I would start by learning those tools first.