It may not be a TBI thing..maybe it is his base personality, maybe more so now after the injury..
Some never fully recover, some may use the injury as an excuse to get away with inconsiderate actions..hard for us to say for sure..
I think you know in your gut already, if this is the path you want for your future..

It's only been a year of dating, that is when you really begin to see the real person and how they are...
you can't change him or fix him.. so you need to think hard before putting in more time..