I get a sense of what you are saying on the trust thing. I like to think I would/could learn to trust again with my H. But even now, every time I see him on his phone or see him texting with it in my presence, my first thought is HER. Even if it is work, I still go there in my mind...so I can see what you are saying. It has to be hard.
I hope he is supporting you and helping out with you and with the kids while you are focused on your mom. Take care.