Hello CharcoalGray: Welcome to PsychCentral! I can't say that I have experienced anything exactly as you describe. However I have struggled for many years with intrusive thoughts as well as what I will call "compulsions". (I'll spare you the details.)

I've seen a few therapists for brief periods over the years. But I never really got into any of this with any of them... not that I think it would have done much good anyway.
In an effort to allay my intrusive thoughts, I employ a Buddhist practice called "compassionate abiding". This involves simply allowing the intrusive thought to come forward... breathing into it... perhaps even smiling to it. Sometimes I will even place my hand over my heart as a sign of lovingkindness & compassion for it. After a few breaths, I then drop the "story line" (whatever is actually occurring at the time) & simply continue to stay with the underlying emotion... be it fear, anxiety, grief or whatever allowing it to fade at its own pace.
Two things happen when we employ this practice. First, very gradually over time, the strength & frequency of intrusive thoughts wanes. But second, & perhaps more important, is that we learn we can stay with difficult thoughts & emotions without losing our balance... our equanimity. Here is a link to that mental-health-oriented description of the practice of compassionate abiding *Laurie* referred to:
https://mindsetdoc.wordpress.com/201...e-abiding-101/
May it be of benefit.
By the way, compassionate abiding is one part of a larger ancient Tibetan Buddhist practice called: "Lojong" which translates as "mind training". If you're interested in learning more about this practice, I highly recommend the books of the American Buddhist nun Pema Chödrön... in particular:
Start Where You Are- A Guide to Compassionate Living .