How to help an overreactive person, who is upset with God when life isn’t peaceful

I see my husband suffering with a couple challenges. We’ve been together over a decade and it’s been persistent. He’s been through a lot in life which is why I partially understand his first challenge below, but I feel so sad about the second challenge and I long desperately to help him. Is there anything I can do, besides prayer?

Two challenges:

1. He explosively overreacts to everything, treats many situations ( that I would barely bat an eye at) as emergencies.

2. Gets upset at God when he feels blessed and at peace (when life is well) and as soon as he feels this, something “terrible” happens (which could either really be something not good, or something he overreacted from)

I discuss with him that we must experience suffering to become more experienced, patient, compassionate, etc., and that God is always a constant. And if we always live “well” then we won’t grow spiritually. And secondly that he should try not to treat everything as an emergency but acknowledge the emotions and move to a “response” after initial reaction. He reacts so badly to such little things that his whole day or even few days get ruined, and even physically he gets back pain from it, and it affects the atmosphere in our family. He feels intense anger, grief, offense. It could even be over something like yesterday my sister in law let our kids out to play for 20m in sub freezing temperatures in thin sweatpants despite us leaving a bag of outdoor clothing. When he saw it, he panicked, yelled at everyone (kids, sister in law)and is anxious that our kids might have health problems. He sincerely never wants to leave our kids with our SIL ever again and feels like the relationship with her is permanently broken now.

But he gets hurt when I try to talk to him about this all and probably some trauma surfaces. So I try more to just listen now.

We don’t go to a church yet because we recently moved. He doesn’t believe in counseling/therapy.