It is rare, though I suppose not unheard of, for it to happen with younger, healthier people. It is, in fact, a loss of will to live that the body might be suceptible to, but moreso if the body is ailing already in some way.
I never heard of someone dying from Broken Heart Syndrome when a spouse turns to the dark side of the force ... so I still find Padme's death from No Will To Live among the most retarded things I've ever seen in a movie.
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