The porcupine dilemma is an analogy about the challenges of human intimacy. It describes a situation in which a group of hedgehogs all seek to become close to one another in order to share their heat during cold weather. However, once accomplished, they cannot avoid hurting one another with their sharp quills. They must step away from one another. Though they all share the intention of a close reciprocal relationship, this may not occur for reasons which they cannot avoid.

source: Lovely Wikipedia