Nobody grows old merely by living a number of years. We grow old by deserting our ideals. Years may wrinkle the skin, but to give up enthusiasm wrinkles the soul. – Samuel Ullman
Your 40s are a major trough. About the age of 50, feelings of satisfaction begin to rebound and keep rising into your 50s, 60s and 70s, with health being a major factor. – Jane Pauley