You may not control all the events that happen to you, but you can decide not to be reduced by them.

This quote means that although we cannot control what happens to us in life, we can choose how we react to it. We can choose to be unaffected by the events we face, to not allow them to reduce our resilience or strength. We can choose to cope emotionally and mentally, to stay strong and remain unaffected by the things that happen to us, instead of feeling as if situations have control over us.