Compassion Fatigue
A depletion of the capacity to care, specific to people in caregiving or helping roles, first named among nurses and now used across therapy, social work, and rescue work.
Compassion fatigue was named by researcher Charles Figley to describe what happens to professional helpers who absorb other people's trauma as part of the job — a kind of secondary traumatic stress layered on top of ordinary burnout. It is not the same as empathy fatigue in general, which can happen to anyone; compassion fatigue specifically describes the caregiving professions and often includes trauma-like symptoms, such as intrusive thoughts about a client's or patient's suffering.
The standard response is not to care less but to change the structure around the caring: supervision, peer debriefing, and caseload limits that give the nervous system recovery time between exposures, since the damage comes from the absence of recovery, not from caring itself.