My TMJ is/was not quite as bad as yours is right now, but I have had quite a journey with it. So I am sharing some of my experiences in hopes that something might be of help.
I visited a Physical Therapist who specialized in TMJ and it was a life-changing experience. She worked on many levels, physical & emotional, hands-on and talking/teaching. She would work directly in my mouth, which was mind-blowing - i had never had anything like that done before. And she would work on the associated muscles in my head, neck and back. She taught me some techniques for dealing with the extremely tight muscles myself - i.e. how to specifically massage specific muscles in my jaw area (tiny little tight individual muscle).
My dentist referred me to an Oral Surgeon, who referred me to the PT after I told him I didn't want surgery or drugs of any sort. I probably saw her for about five months. The problem did not completely go away, but it did get better and I gained an incredible sense of mastery of hte problem - that I could actually do something to improve it.
Then, on her advice, I started doing more swimming, which relaxes the neck and back area. Also yoga. These are both stress-relievers and also stretch out the various muscles that contribute to TMJ.
However, my problem never completely went away. About seven month ago I started seeing a traditional chinese medical dr. She did acupuncture that specifically addressed TMJ, and also did Gua Sha, which is a traditional home therapy for ridding your body of toxins. This also helped, but did not completely rid me of the problem.
Over the past 2 months, I think I have found a major part of my solution. I had all of my silver mercury amalgam dental fillings removed, in four separate visits (because there were such fillings on all four "corners" of my mouth). With each visit, my TMJ actually got a little bit better. After this last visit 3 weeks ago, my TMJ is almost completely gone. I am amazed.
I have two theories about why removing my amalgam fillings has helped my TMJ. First, I think that the mercury in the fillings has been an irritant - and that perhaps my clenching/grinding was a subconscious attempt to "bite it out" of my system?
Second, now that I have the white, harder fillings, and have gone through a few sessions of "bite adjustment" - during which I talked to my dentist about what an ideal bite (tooth placement/touching) should be...I suspect that my old fillings were too large, causing my molars to touch inappropriately. My theory is that because my back teeth were in effect "too large" that I again was trying to "grind them away". But of course, because there were fillings there, that was impossible.
Also, grinding of the amalgam fillings releases a stream of mercury gas, which is toxic....there are sites on the internet that discuss this (sorry don't have the links handy right now).
After my fillings were removed, I had a sinus reaction which I learned corresponds with mercury toxicity, so I suspect it was my body ridding itself of the last toxins?
Again, I am not an expert on this, but these have been my experiences and observations about my specific situation. I feel that I am well on my way to kicking the TMJ problem - finally - and hope that your situation improves very soon too.
ETA:
I have had splints int he past and found that they did not help as I only clenched more. Also, the self-massage techniques provide instant discernable relief. It is just not permanent because the muscles have to relearn themselves into new patterns...and in the short term, will eventually go back into clenchign mode.
