In order to explain what love is, Kabbalists use the example of the love of fish.
To love fish means to eat them, or in other words, I love to use them for my own personal benefit. To live as a fish means to be satisfied with what you have. Fish live simple lives of self-sustenance: to eat and reproduce. A person who reaches despair in our world starts discovering that his/her attitude to others is one of "love for fish," that others cannot fulfill him/her, but that there's got to be something other than this, a place where "true love" exists. That there is something beyond this world that he's attracted to, and gets his fulfillment from there in endless power and intensity, and then the sensation of love encompasses a person entirely.