If there is any news to it, it's our society's continued isolation. We didn't evolve in such lonely existences, far from family, friends, and community. Our ancestors who outlived partners depended on them, and prepared for such outcomes by seeing it happen to their elders. Identifying the problem this way might lead us to reduce our isolation.
But this piece didn't touch on that angle.
Being triggered with memories of your loss every time you go to the supermarket, not eating properly to the point of experiencing easily avoided physical problems...
It is probably hard for many to understand until you've been there.
Men typically end up more emotionally dependent on their wife. When a marriage ends, women are usually financially devastated. Men are emotionally devastated and don't know how to recover.
Women tend to be more emotionally savvy than men and tend to have better social support systems. Men tend to be heavily dependent on their wives for emotional support.
So do a bit of that and, if necessary, encourage your your partner. It might also be possible to encourage friendships you brought into the relationship to grow to the point where they would work independent of you.
Sometimes this obviously is an effect of having children and therefore not enough time. But, even then, giving it a higher priority should make it possible at least to maintain existing relationships over the decade or so children take the most time. I also know plenty of couples with children that value relationships and have found any number of ways to accommodate them, from changing jobs to cut down on commutes to getting multiple families together for activities they would usually just do with their children, etc. For the really adventurous, the it-takes-a-village approach to raising a child also seems to be making a comeback.
Speaking of free love: It seems (if Hollywood is to be believed) that in the US, people sometimes frown upon their partner having any friends of the opposite gender. While it's possibly too much to ask for people to completely free themselves of jealousy, one should at the least not consider such a policy to be a small ask to make. That's especially true for friendships that started before the couple even knew each other.
I can't say I've got that impression from US movies, but watching the Chinese dating TV show "If You Are The One" (airs in primetime with subtitles in Australia), the women often ask the male candidates to give up all their female friendships as a condition of dating. (Occasionally the male contestants will make the same request.) Sometimes the women will allow female friendships if the male contestant agrees to regularly let them read/approve the phone messages they send to others. It's been an interesting show to watch from a cultural perspective.
But it strikes me that being in a committed relationship, married or not, removes a portion of one's life from conversation. It strikes me as awkward to speak in a much more than neutral tone about one's spouse. This really goes for conversations with the same sex as much as for conversations with the opposite sex.
I'm pretty sure it's not a good thing, but hey at least they won't feel the pain of dining alone /sarcasm.