If you want to see how he is.... call. If you are content not knowing....then don't call.
I agree. You do what you need to do for you, and the kids, and then applies to calling there too. You cannot even begin to take on trying to educate those people right now! It is time to focus on you. You have your own recovery to work through, which is what you need to do in order to have a healthy relationship with him should you choose to stay together. It is not selfish of you to be working on a better you, it is the best thing you can be doing for him, and for your children.