I want to say I hear you
Its just so exhausting, so consuming, that it does get to the point of - well I may as well
3 attempts, and many a walk around the park with the dog thinking if only I had the courage to use the lead
I spent many a night in a phone box to the samaritans ( back in the day before mobiles )
Counselling was my saviour - and medication. Actually I ended up in full time group therapy for 6 months and three years of twice weekly sessions
You do need to tell your psychiatrist and /or therapist, they cant help unless you do, but at the same time I totally get why you dont - I could never engage, which is why group therapy worked so well for me. No hiding, no dodging. Things I had buried so deep came to the surface and in a very supportive environment of others with the same/similar experiences really really helped me start dealing with them
Now I can say I have been free of those thoughts for over 20 years. I still need meds, but Im stable as in I dont go down those rabbit holes. I still have episodes of depression , but I get through them pretty unscathed . The understanding of myself that I learned in therapy keep me going now
Please ask for help, there is help, it can take a while to find the help YOU personally need, but its there