“The issue is anything external may help for a little bit but ultimately these feelings come back.”
yes, well, that suggests the problem is internal.
when i found myself in that place (though it took me longer to get there than you), i decided to do the 12step program, though i had been sober quite a while. i decided it would likely , if applied, lead me to take care of my discontentments, resentments, harms i had done and needed to clean up, and give me a way to prevent me from adding new messes.
turned out to be so for the most part.