i will look into it
and thanks for sharing your story.
i am not a doctor,
but a girlfriend of mine had this, too. apart from the sleep deprivation in your boyfriend you should understand that you damage your own teeth, most of all.
you should probably go to the dentist as soon as possible.
my girlfriend got occlusal splints given to her. she had to wear it at night.
it is probably true that there might by psychological reasons for this, which you have to sort out by yourself,
but at least the splints will help you prevent any further damage.