My ex-h quit his job when I was 32 weeks preggers with my oldest. I made him apologize to his boss, explain that he'd just turned 40 and that it was all the stress of the unknown of a baby.
How badly, was your husbands quitting? I agree, about prioritizing. Perhaps the stress of a new baby coming into his life, is terrifying?

fyi:add: that was also, during the first year of marriage