Perhaps the best definition is, "Learned helplessness is a phenomenon in which individuals gradually, usually as a result of repeated failure or control by others, become less willing to attempt tasks." It may occur in everyday situations where continued failure inhibits an individual from experiencing faith in the future. Apathy and submission prevail if and when life circumstances cause the individual to experience life choices as irrelevant.
It's my belief that all of us, regardless of station in life, success or ambition, experience moments and days that reinforce our feelings of helplessness, and a percentage turn to addiction for relief. Those of us who have done just that, and later discovered that the addiction itself had become the focus of our helplessness, are in a special quandary. We turn to other forms of relief--some write, some sing, some dance, some medicate--because, in the words of Blaise Pascal, "Man finds nothing so intolerable as to be in... without passion, without occupation, without diversion, without efforts. Then he feels his nullity, loneliness, inadequacy, dependence, helplessness, emptiness."
Pascal was a mathematician and physicist in the 1600s; he invented the world's first calculator, the pascaline, and throughout his life was plagued by ill health. He struggled with LHT long before it was defined, and of course, he was French.