I agree with you nimbus. His marriage quotes include Chekhov:

If you are afraid of loneliness, do not marry.

and Rilke

the highest task of lovers is that each stands guard over the solitude of the other

Really? I don't think so.

You are right that his main point was to emphasize the difference between loneliness and solitude and I agree with those points. As flagamuffin knows, I'm the cheerleader for periods of solitude. This article says

Loneliness is the pain of being alone, and is damaging. Solitude is the joy of being alone, and is restorative, even empowering.

I like that he refers to the evolutionary theory of emotions. Fear, for example, evolved to protect us from danger; guilt evolved to encourage us to measure our behaviour against our beliefs. Loneliness, he says, evolved to motivate us to seek out social bonds which potentially protect us from danger in a scary world.

Along with other social scientists such as Sherry Turkle Alone Together he suggests that the comforts of the Internet are inauthentic:

The internet has become the great comforter, and seems to offer it all: news, knowledge, music, entertainment, shopping, relationships, and even sex. But in the longer term, it stokes our envy and longing, distorts our needs and priorities, desensitizes us to violence and suffering, and, by creating a false sense of connectedness, entrenches superficial relationships at the cost of living ones.

In terms of hubski, I have to object. The sense of connectedness I feel with my hubski friends is not false. But it is a different kind of connectedness than I might feel for my neighbours. We are capable of many many kinds of connectedness. If I was stuck in another city, I'd ask my neighbours to come by and feed my cats. But if I was stuck in an ethical dilemma, I'd probably ask hubski for some ideas.

I have a serious problem with this section of the article:

All these parties (he's referring to managers, doctors, "stakeholders" of all kinds) train in communication, negotiation, and conflict handling skills, and schedule time and organize activities for team building, group bonding, and networking. Yet they cannot find the opportunity or humanity to listen, think, or feel, or even to exercise elementary common sense.

That seems to be a carelessly overgeneralized statement. This author could make his points better without dismissing managers of all stripes.

A final note on marriage. The author says

it is common to feel lonely within a marriage because the relationship is no longer validating or nurturing us, but instead diminishing us and holding us back.

Indeed, this is an argument for finding a partner that offers endless possibilities. After experiencing relationships that diminish you or hold you back, move on to something different not more of the same -- I think some of you perhaps know of what I speak: b_b insomniasexx _refugee_, and I would add myself to that list.