Marrage
We can have anything in life we want but not everything. Spouses will sacrifice a lot for each others but an imbalance will lead to a dissolution in most cases.
The purpose for marriage is to create a union of forces for common goals. Usually that means children, home and mutual support. A pilot can not offer much to a marriage these days, they are gone a lot, have unstable working conditions and do not have the financial means to add much to support the household. It often is an inequitable situation for the non-flying spouse.
The net results are that increasingly pilots are forced to choose a single life or will become single very soon. 20 years ago it was possible for a guy in his 20's to get hired by a major and reach a stable place in the seniority list by the time children come along. Back then pilots were home much more and earned a very good living.
It seems that now pilots can choose between a family life or a flying one. It isn't a spouses fault. It is a two way street. A pilot must be able to be an asset to a marriage.
SkyHigh