I truly hope your 12 year old can get past this. I think youve done the exact right thing. While I've never been thru anything like what you are going thru, that's always been a fear of mine. I've always wanted kids but to have one of them be in a condition like this where they will never develop any sort of quality of life. And like you said on the flip side (probably my biggest fear) if i was trapped inside my body with literally no way to communicate I would go insane, quickly.

Long story short, if I was in your position I couldn't imagine myself doing anything different than what you have done. And I truly hope that you can get some comfort from reading this and the rest of the comments.