Glass

El amor es difícil porque las emociones humanas son como el vidrio -- son delicadas, pero también se pueden cortar.

My spontaneous response when asked to write a thought about love at the beginning of Note to Self, a student production in UF's theatre department that consisted of monologues of the actors' varied experiences with love and relationships, which note then joined the hundreds of others on the studio wall that had been collected during the piece's run.

Translated:

Love is difficult because human emotions are like glass -- they're delicate, but they can also cut.