I'd suggest having your partner see his doctor and talk about what has happened over the years. Maybe he/she will suggest having and MRI done to see what's going on inside his brain. If the doctor doesn't suggest it, I would request it. Same thing if he ever ends up in the ER again with a head injury. I'd ask for a CT Scan or an MRI and be sure to mention his past injuries. Maybe that could be the first step in the direction of some answers.

I'm sorry you and your partner are dealing with all of that. Hopefully this is helpful to you.