Mate, it sounds like you handled it like a pro!
I had a similar situation when my daughter was about 8 or 9 and my cousin who is not actually in recovery but is well experienced with AH's told me it was ago to say "I don't know" when it came to her fathers crazy unreliable behaviour.
It also helped me to learn that children are basically self centred and think everything that happens is a reflection of them, it relieved me of a lot of guilt I felt that was certainly misplaced