I've been on 350mg/day Wellbutrin for ages with no discernible help.
Well except that on the few occasions I've dropped it (cold turkey, quite painless FWIW) I noticed after a week or so I noticed I was a tad worse, so I went back on. Perhaps I should I should go off for the sake of reducing my very lengthy med list!

You may be interested to learn that I've finally -managed approved my doing a trial of buprenorphine (patch form - expensive! 🙁 ). That is after 20 years of research and waiting for the Psychiatric Industry to come 'round to legalizing it (they did!).

It probably helped me getting it approved, that I was already taking an opiate, hydrocodone, for chronic pain, and I'll be replacing that opiate with buprenorphine for both pain relief and TRD - treatment resistant depression.

I've long been convinced my brain has too little dopamine (which this will contain) rather than serotonin which is the basis of most modern antidepressants. (Undoubtedly why NARDIL an MAO inhibitor, was so wonderfully effective for me - heartbreaking that I had to discontinue it owing to a side effect which just happened to be harmful for me.

However, wherever the subject arises, I try to make time to call attention to the dopamine hypothesis to treat depression as I feel sure many who suffer from treatment-resistant depression like me need dopamine rather serotonin.

The buprenorphine is brand new for depression, though it's still considered somewhat experimental for old school psychiatrists. Has been used mostly for detoxing opiate dependent and also for pain. (Google: buprenorphine, Treatment resistant depression)
That said, there have been many clinical trials of buprenorphine to treat TR, but however effective it is, it hasn't been used largely because of the national opiate hysteria.

Good luck finding relief for your pain - likewise for others who struggle to find relief for psychic pain!