languish

To lose strength and become weak; to be in a state of weakness or sickness.

We […] do languish of such diseases.

To pine away in longing for something; to have low spirits, especially from lovesickness.

He languished without his girlfriend.

To live in miserable or disheartening conditions.

He languished in prison for years.

An elderly Hungarian found languishing in a Russian mental hospital could finally be allowed to return home - 55 years after being taken prisoner by the Russian Army.

To be neglected; to make little progress, be unsuccessful.

The case languished for years before coming to trial.

To make weak; to weaken, devastate.