I think we need people plural. I think it can be unwise to need a particular individual.
Humans are a social species. Very few of us have the necessary psyche to cope in social isolation. Our relationships with friends, family, colleagues etc are what define us to a large extent. The presence of those relationships, when positive, have a strong bearing on someone's mental health, and their absence can mean the difference with coping with a mental illness and going under in some cases.
We all need people in our lives.
I think in the past, before the nuclear family became the dominant social building block, peoples relationships were probably less intense on an individual level but broader. I also think this particularly affects women.
In the past, many women had a network of female support to call on from their mother, MIL, sisters, etc because of the extended family norm. Men also had that but they also had, and continue to have, social groups outside of the family. As the nuclear family has taken precedence, women have become more isolated because they've lost that extended network and have taken on all the subsequent responsibility for . Even on MN how many times do we have posts from SAHMs whose DH/DP is out with his golf/pub/work mates on a saturday while she's at home with the DC etc.
Of course, in some cases we have SAHDs and not everyone had a good extended famil - for some women losing the MIL has been a blessing
- but I'm talking about social norms as a group, not individual cases.
So I think for many women society has actively encouraged them to need just one person - their DH/DP. Isn't that what the spin is about "the one" etc? And, if you're lucky enough to meet the right person and have a good, healthy relationship, that "needing" someone can work out quite well.
Ironically, as people age, I think it tends to reverse. As children grow up, women seem to broaden their network, often through their children, while men can often find on retirement that theirs has dwindled to nothing.