Maybe creating a log of the work you do would give you some measurable objective points for your own self worth? I did that at my last place to establish their PIP was pretextual. It kept me around long enough to find the next place. But it also built my self confidence - by having an undeniable, immutable recount of my work. I’d keep a running log each shift and email it to myself at the end. Everything time stamped, dated, summarized, and relevant documents included.

IT support and now sys admin/engineering stuff.