I’m slowly learning not to let my happiness depend on other people.

In civilized life, where the happiness, and indeed almost the existence, of
man depends so much upon the opinion of his fellow men, he is constantly
acting a studied part.
     Washington Irving

All the world’s a stage,
And all the men and women merely players:
They have their exits and their entrances;
And one man in his time plays many parts.
     William Shakespeare

Just as a cautious businessman avoids investing all his capital in one
concern, so wisdom would probably admonish us also not to anticipate all
our happiness from one quarter alone.
     Sigmund Freud

When one door of happiness closes, another opens; but often we look so long at the closed door that we do not see the one which has been opened for us.
     Helen Keller