To stay or not to stay..

Ok, I have a real problem and I can tell I'm running out of time to make a decision😟. I was married just after my 18th birthday to my high school sweetheart❤💍. It was rough financially but it was worth it. We were happy. about 6 months into our marriage, we started to clash (I'm a Virgo, he's a Leo). He started to become emotionally detached and depressed, and that quickly turned to emotional aggression toward me. Just over 2 months ago, my man and his brother were in a motorcycle accident that killed his brother and almost took his life as well. I spent over a week in the hospital with him and never left his side unless my friends took me out to force me to eat and get some air. Ever since this happened, it's gotten worse. One day he's the perfect guy, and I can't picture myself without him, and the next moment it's like some kind of switch was flipped and he turns dark and angry. It's gotten so bad and I'm trying to stay patient and understand his situation, but it's out of control! He fills my head with horrible things and makes me feel like sh*t, then the next morning it's like nothing happened and he wants to hold me and love me again😒. I have tried getting him to see a therapist, but he's more worried about what others will think of him. None of my friends like him anymore, and I hate myself for this, but lately I've started to think about moving on without him. I feel like I'm being used and manipulated and that scares me a lot (both his parents should have been put in a loony bin a long time ago, and I'm afraid he may have the same mental health issues). I'm not happy, but at the same time I can't convince myself to walk away. I want our marriage to work out, but it may be too late. Thoughts and advice would be greatly appreciated, I feel like I'm going crazy!!!