Hi, it may have already been stated but I strongly encourage you to find a support group. There may be ones specific to peers and family support for head injuries. Even a caregivers support group might help. So too I think a Mood disorders group which would help with the anxiety and depression. I wish you so much luck. I have seen personally a loved one become the cruelest most foulest person I have ever known owing to sudden onset of dementia and how the fall-out affected everyone.
Look, you absolutely need to care for yourself. Don't feel wretched for that. Be compassionate to yourself.