Terry Eagleton at The Guardian:
Solitude is not the same as loneliness. Lonely people feel the need for company, while solitary types seek to escape it. The neatest definition of loneliness, David Vincent writes in his superb new study, is “failed solitude”. Another difference between the two groups is that hermits, anglers, Trappist monks and Romantic poets choose to be alone, whereas nobody chooses to feel abandoned and bereft. Calling yourself “self-partnering”, meaning that you sit in the cinema (should they be open) holding your own hand, may be either a genuine desire for solitude or a way of rationalising the stigma of isolation. The greatest difference of all, however, is that solitude has rarely killed anyone, whereas loneliness can drive you to the grave. As the coronavirus rampages, some of us might now face a choice between physical infection and mental breakdown.