I found an academic article that argues "The empirical results show that unemployment seems to be an important factor behind marital instability. However, only unemployment of the husband has an effect, and this effect is immediate." (HT: I can't remember exactly how I found it, so I can't give a hat tip at the moment).
Since my own divorce coincided with a period of unemployment (followed by a brief period of part-time employment), this may be part of the explanation.
Actually, my ex-wife once heavily implied "Well, if I divorce you, I get guaranteed income for as long as I have the kids, but if I stay with you, I might get dragged down into bankruptcy if you don't get a job and can't pay off your loans."
From an economic standpoint, what she did makes a lot of sense. As my lawyer said "Unfortunately, the state doesn't care whether you starve to death, file bankruptcy, or are otherwise ruined financially for life. The no-fault divorce laws are written so that the wife gets the kids and the money, and the state can't really take into account whether or not you have a job or debt."
I don't mind paying child support, but I have to pay alimony AND her attorney's fees. And now she gets the kids (they can visit me twice a year - we're still working on that), guaranteed income (or else I become a "deadbeat dad"), and doesn't have any real expenses (since her parents, who have been trying to get her to leave me for years because I never earned enough money for their tastes, are putting her up and have told her she can stay with them for the next several years).
Anyway, if you're going to lose your job, make sure your marriage is 110% solid if you're a man. Even then, it may not help. Another reason to avoid any and all debt: if you do get divorced, you just added another massive round of debt you cannot avoid.