Hi Lost. I read you post and I want to share some insight, in order to try to give you a little different perspective, if I could. Look, I'm not criticizing or judging you. My intent is to put some light to help you. So...
Look! You're not the one. I'm self taught. And the parrot in the corner house speak English better than me!
You are limiting the level you can reach by adopting a closed mind, a belief that surely is not aligned with the reality. I believe you can find alternatives and sharp yourself. The only limit in this terrain is the creativity. You don't need to use the same path that works for the majority of people.
I relate about you battle to have mental energy, In my case this battle is more related to sleep time, stress, anxiety, bad habits, etc. I understand you brain injuries, but I would try to find another causes for the lack of energy (even nutritional), or try to develop some habits that improve you brain energy. Sometimes the focus in a well known problem creates a blind spot from another ones or alternatives to overcome.
Friend, I understand your pain. But look, you have a daughter! How can you long for death!? I know surely I'm being cliche but your daughter may be one of your reasons to fight, to win, to overcome!
Feel free to message me if you wanna vent or talk about these things.
