defeatist
/dɪˈfiːtɪst/Definitions
1. noun
A person who has a tendency to expect the worst and give up easily, often in the face of adversity.
“The team’s defeatist attitude led to their downfall in the championship.”
2. adjective
Pessimistic; expecting or predicting failure or defeat.
“The defeatist outlook on life can be overwhelming and affect mental health.”