Marriage is a fairly “greedy” institution—married people tend to invest less time in their relationships with friends, extended family, and the broader community. […]
And while its effects may be felt by those who remain single and find their support networks weakened as their married friends become less available, it hardly serves the married that well either, as recent articles on the difficulty of making and maintaining friendships in (married) middle age attest. No wonder people whose spouses also happen to be their best friends get such a greater benefit from marriage than others. For some, this particular “super-friend” may well be one of the only close friends they see with any regularity—it helps to really, really like them.
Looked at from that angle, the fact that marrying your best friend seems to make middle age “slightly less terrible” (as the headline of the Washington Post’s coverage of the study sardonically boasts) seems less a ringing endorsement of marriage than an indictment of the way many of us spend our middle age—in socially isolated domestic units, each consumed with the nearly impossible task of balancing work and family, made bearable only by having a close friend in the trenches with us.”
— Maya Dusenbery, Benefits of Marriage Study Hints at the Horrors of Middle Age, in Pacific Standard