Wow, Chrys, that sounds awful.
I've been grinding and clenching since I was a teen, too (which I now attribute to major orthodontic work to fix an overbite). My teeth are flat now, and in the last year I've had to get 2 crowns. I also wear bite guards -- the kind the dentist has made -- though they don't stop my grinding+clenching, they just protect the surface of my teeth. When I'm really stressed, the jaw pain is horrible.
I saw a TMJ specialist years ago -- $700 and not covered by regular or dental insurance -- and she solved nothing, despite her assurances. So I'm averse to specialists. I feel like there's a lot I can do to lessen the intensity myself, including yoga, breathwork, meditation, etc. Kundalini has been especially great for me, because of all the breathwork (there's even a kriya in which you're supposed to clench your teeth
but I refuse to do it). I wish there were a guided meditation CD just for this. One that I could fall asleep to & maybe internalize.
Adding to the teeth-flattening, I also drum my teeth when I'm rushing around doing too many things.
I get a song in my head and start drumming to it, with different teeth making different drum sounds (molar = base; fangs = snare). I thought other people did this, too, but when I told my former dentist about it, she looked at me like I was a Martian and told me I needed to wear my bite guard during the day. Um....
NO. I stop drumming when I realize I'm doing it, but sometimes I don't realize immediately, when the song is good & I'm rocking out.