Burnout

Burnout, from merriam-webster.com:

Definition of BURNOUT

1

: the cessation of operation usually of a jet or rocket engine; also : the point at which burnout occurs

2

a : exhaustion of physical or emotional strength or motivation usually as a result of prolonged stress or frustrationb : a person suffering from burnout

3

: a person showing the effects of drug abuse

Ironically, two of the example sentences are "Teaching can be very stressful, and many teachers eventually suffer burnout." and "... the burnout rate among teachers."

Burnout, from Wikipedia:

Burnout is a psychological term for the experience of long-term exhaustion and diminished interest.