sorry to hear you’re suffering. I have ptsd that’s triggered in medical environments so I do understand.
I find it difficult to still my mind and find common eastern practices useless for me.
what really helps is gentle movement, body awareness exercises and what’s called discursive meditation best.
Yin yoga is great at releasing any trauma, it’s gentle and nurturing. Body awareness exercises (there’s loads on you tube).
Discursive meditation is really helpful. You think of a simple object to start eg a triangle then think of everything to do with that shape, are the corners sharp, what does the number 3 mean to you, does it look strong? Any thoughts that come to mind about the triangle. If your mind wanders, just slowly trace your steps backwards until you get back to the triangle.
Try breathing exercises, simple box breathing, again look on you tube, practice slowing your breath down, breathe from the belly, breathe in for 4 out for 6 in for 4 out for 8.
hard exercise can be difficult if you have anxiety as it increases your heart and breathing rate and sometimes your brain will trick itself into thinking it’s a panic attack, you can’t breathe or you’re having a heart attack. But for others it helps.
the jerking when you fall asleep is probably linked to not feeling safe and therefore trying to keep you awake. If you don’t mind me asking, do you dissociate much, not feel connected to your body fully?
Singing Vowels in an elongated way is a good way to stimulate your vagus nerve and therefore quieten the flight or flight mode.
Treat yourself well. Love and niture yourself