During my working period I kept quotes all over my desk and when I thought that a quote needed a constant reminder I would frame it and put it on my desk. In times of difficulty I would review my quotes, derive comfort, and move in the right direction.
One of my favourite quotes:
"100 years from now, it will not matter what kind of car you drove,
what kind of house you lived in, how much you had in your bank
account, or what your clothes looked like, But the world maybe a
little better because you were important in the life of a child."