The essential sadness is to go through life without loving. But it would be almost equally sad to leave this world without ever telling those you love.
When you hold someone, hold them like it's the last time you will ever see them and when they go, don't make reasons for them to stay... only reasons for them to return.
There would come a time when we have to stop loving someone not because that person has started hating us but because we found out that they'd be happier if we let them go.