Yesterday he even said he was just gonna stay and buy a house there.
... in which case you might want to think twice before saying you'll do whatever it takes!
Seriously, I think your commitment is wonderful. I also agree with what others have said. I think it's enough to express your support for him in this moment, and your willingness to be there for him when he gets back. You don't need to anticipate any outcomes or predict your future feelings, and I think it's better not to - apart from any other reasons, it reduces the pressure on both of you.
Something I'd be careful about is trying to do it for him, or to help with things he can - and should - do for himself. He needs to go to counselling on his own. (Unless it's couples counselling for your relationship, which would be something different from trauma counselling.)
I think it's great that you say that you take it seriously.
I also really like that you said:
I know i have no clue what you're going through, or have been through.
I think this is a very validating way to show your support without saying you understand things that you can't.
Your love shines through. I think he's very lucky to have your support. I just hope he appreciates you! Make sure he does, and remember to take care of yourself and your own life as well as supporting him.