Hi Bella, welcome aboard!
For what is worth you have made a great start by wanting to learn about this & what you can do to help your hubby.
I have just gone past the 2yr mark with my hubby & believe me I'm still learning & stuffing things up as to how to respond to things so don't be so hard on yourself.
The one thing I will ask you to thing about is going to see someone for yourself. I went to see someone because I had to grieve for my hubby as he will never be the man I thought I was going to be married to. (his accident happened the day before our 1st wedding anniversary)
Just remember that although it sucks seeing them in so much pain & turmoil if you don't look after yourself it will only make things harder on both of you.

take care