Good to hear that you are starting your plans for you and your son - the getaway bags are a great idea. I'm sad to hear that your AH is hiding from being honest with your son about what is going on. At 13, he's old enough to figure things out but young enough to not know how to deal with them maturely. This puts him in a tough spot. Do your best to comfort your son & be as honest as you feel you can with him about what is going on - he likely already knows, but I think it would bring you two closer and you can help to support each other better.
Hope you have a wonderful, peaceful weekend.