In view of the new pathological perspectives, have you reviewed your treatment goals with your therapist?
Does your therapist know this, know how you feel?
What is your vision of "peaking out" respectably?

I cannot offer you advice, Ygrec, for mine is not a depression success story and the nature of my depression may be different from yours. As interesting as insights into my remote past may be, I have no confidence they will produce realistically actionable results in my present.

Nevertheless, I keep puttering along at a low level. This puttering is not what I regard as respectable, but the meds and depressive loss of affect mollify the sting. Maybe I'm not much different from one fogged on the way to death.

History is interesting and instructive. Yours, and that of your family, may be exceptionally so.