Can you journal as you would speak if you saw him? I assume you go from one topic to another so maybe pick the topic you would talk about first. If you journal too much then some of it may get lost and never addressed. I am sure you will recognize when that is happening.

I think it is a good idea to write about things that you don't talk about when you see him as they need to be broached at some time.

Good luck in writing. I think it helps tremendously.