I Have A Husband Who Was Under Extreme Work Stress

I have a husband who was under extreme work stress a number of years ago. As if a dimmer switch was on him he started not smiling, being angry, stopped speaking my name and avoided bodily contact with me and kids. Became mean and cold. Has told me that I attach him or the kids put pressure on him by being loud. I bent over backwards to make changes but nothing helped, he was always dissatisfied. He had nightmares, some delusions like believing there were rattle snakes in the yard (Cicadas) and even that I tried to kidnap the kids because I didn't bring them with me to pick him up at the airport.
His face would change whenever anyone was around, smile be polite talk positively and then when we are alone angry face at me, negative all of the time. His anxiety is pulpable. Never any physical violence. He is successful at work. I am trying to find the right treatment for him. It is like there was a chemical rush release in his brain to change him so quickly and lastingly. Any thoughts of directing my research?