Yoda made fame this quote. If you remember him in start wars. This is also related to the spiritual law of universe "detachment".
We always get depression when we lose the things or people we are attached to, we love. Attachment to things or people, itself is a weakness.
A man to be powerful, should train himself to let go of everything or anybody he fears to lose.
Love is natural, and to love each other is a law above all laws. But no one was ordered to attach to whoever he or she loves.
Some relationships fail because of this attachment, you love someone and attach to him or her to the level he or she asks himself or herself "is he or she really my type or I just made a wrong choice?"
Nothing is supposed to last forever so attach to everything as a temporary thing. When you love don't get to too much, when you're working hard for money, train yourself to let them go, and so on.
Detachment is not lack of responsibility but the real power to work for what you want and to accept the results of your hard work.
Thanks for your time reading!
By Jado
SHALLOM