Restraining our desires, chasing pleasures, indulging in alcohol, using sex as a hobby, especially promiscuous sex, overeating - this is all an aimless loss of energy, which empties a person and deprives him of the ability to adapt.
In order to adapt we need love.
We need the energy which comes through love. In order to adapt, we need to learn to let go of the old and accept the new.
Letting the old go is a sacrifice.
To do all this we need love, energy and detachment, and the ability to sacrifice.
A person who sacrifices, cares, who can share, who feels compassion - this is a person who will receive energy from the above.