Cynics and sentimentalists are at opposite ends of the attitude spectrum. If sentimentalists optimistically insist on looking at the bright side, cynics always expect the worst. They build their pessimistic lives on doubt, distrust, and disbelief.
Either side has its own shadow. A sentimentalist whose naïve hopefulness is threatened can be unexpectedly brutal. This is matched by the doubting Thomas whose shadow side can surface as an unexpected capacity for devotion when converted to a religious dogma.
To live to the full, we must be both tender and tough, ready to accept life for both its beauty and its brutality.