Robert Waldiner shares three core findings in the longest study on happiness: good relationships keep us happier and healthier; the quality of the close relationships are critical (they buffer us from life’s lows, difficult times, etc); and good relationships protect not only our bodies, but also our brains. See: https://www.youtube.com/watch?v=8KkKuTCFvzI    for a fascinating talk and explanation of the findings.