Treatment resistant depression people, what ultimately worked for you?

If you've had treatment resistant depression and found something that works, what was it?

I have been on several psychiatric medications: Prozac, Zoloft many years ago that stopped working; Effexor for about 15 years with only small improvements but I was functioning well; Wellbutrin for a decade but did not feel improvement; Pristiq for about 2 years with minor improvement; the latest, Vilazodone has too many severe adverse effects and I am tapering off it. I have also tried Abilify -- it improved my mood but my blood sugar shot up to unsafe levels.

Last November my psychiatrist started me on lamictal. To make a long story short, it plunged me into a major depression with SI, and I developed new symptoms, severe anxiety and short rapid automatic breathing (cardio and pulmonology can't find anything wrong). I am still struggling with it.

Since then, we continued Pristiq (which lost effectiveness), tried buspirone, lithium, pramipexole, rTMS, and a single psilocybin dose (clinical trial). None of it has worked.

I don't know what it is about the wiring in some of our brains that make us so hard to treat. I am exhausted and terrified.

Two things I won't do: microdosing because there is not enough evidence it works, and ECT, which has memory impairment risks that could affect my job.

If you have had relief from treatment resistant depression, what worked for you? I realize it may not be the solution for me, but I need some hope.