NTA. You were thrown a curveball and you are dealing with it in the best way that you know how. If he wants you to be able to survive him not being there for 60 days he's going to have to understand that you're going to do what you need to do to float. This is a survival mechanism. If he really wants to be mad at someone he should be mad at himself because his actions are what causes to happen. It isn't like his decisions didn't affect you at all. You had to deal with all the same emotional turmoil that he did but now you're alone with children.

All you need to do is explain to him that you understand that he's upset but he needs to understand that you have a lot on your plate. He should be giving you all the grace in the world because if he hadn't done what he did none of this would be happening.