Textbook midlife crisis.
I have seen this happening to many couples who got no kids. Without a family man/woman go purposeless. Thanks to internet, the void in life is being filled with the noise of entertainment.
IMO, any person above 35 should be doubly carefull before getting married. Unless the woman had some really valid reason to stay single untill 31, one should not even be considered. Else the man is walking into a 498a trap.
If the woman is young atleast ina hope of a better life they might be in a hurry to get a divorce and start again. Older women know this is the end of road and , they will squeeze their retirement fund out of the man, if any divorce happens