Looking for answers and help

My boyfriend Carl Langley Belcher of nine months was hit by a truck just over a year ago. His back was broken in 17 places. Since i met him he told me about having seizures. I only recently witnessed 2. But I've found him unconscious multiple times, as he will not seek help or allow for emergency help, I'm having to put the puzzle pieces together. i just recently realised his mid swings and extreme behavioral changes are connected. He sees lights, has headaches, blurred vision, vertigo (born deaf has cochlear implants from a young age). He becomes delusional, easily agitated, complete personality changes, usually just short term memory loss,lately some long term loss. His mother is the only other constant person in his life. When he's"well" he tells her very little of anything. When he's in this state leading up to a seizure and sometimes even after. He lies (to him it may be true) makes it seem smaller, calls me a liar. How can i get him the help he needs,his mother loves him, I'm afraid that if she doesn't listen top me since get him help. He'll either have a stroke (he said his Dr told him this was possible) or the personality changes will stay. In which case i have to leave because he is starting to become physical with me. His well self would never hurt me. I'm not sure how you could help maybe some material that i could share with him and his mother. Please i need to help him. Thank you, Tonya Kloepfer