My favorite Shakespeare Sonnet

The expense of spirit in a waste of shame
Is lust in action; and till action, lust
Is perjur'd, murderous, bloody, full of blame,
Savage, extreme, rude, cruel, not to trust;
Enjoy'd no sooner but despised straight;
Past reason hunted; and no sooner had,
Past reason hated, as a swallow'd bait,
On purpose laid to make the taker mad:
Mad in pursuit, and in possession so;
Had, having, and in quest to have, extreme;
A bliss in proof,—and prov'd, a very woe;
Before, a joy propos'd; behind, a dream.
All this the world well knows; yet none knows
well
To shun the heaven that leads men to this hell.

I had to learn it for a voice and speach class in college. It has stuck with me ever since. I think because it reminded me of my love life at the time.