The King no longer visited her as his mistress, but trusted and esteemed her as a friend and as the mother of his two pretty children.

One day, in the month of April, 1674, his Majesty, while in the gardens, received the following letter, which one of La Valliere’s pages proffered him on bended knee: 

Sire:—­To-day I am leaving forever this palace, whither the cruellest of fatalities summoned my youth and inexperience.  Had I not met you, my heart would have loved seclusion, a laborious life, and my kinsfolk.  An imperious inclination, which I could not conquer, gave me to you, and, simple, docile as I was by nature, I believed that my passion would always prove to me delicious, and that your love would never die.  In this world nothing endures.  My fond attachment has ceased to have any charm for you, and my heart is filled with dismay.  This trial has come from God; of this my reason and my faith are convinced.  God has felt compassion for my unspeakable grief.  That which for long past I have suffered is greater than human force can bear; He is going to receive me into His home of mercy.  He promises me both healing and peace.

In this theatre of pomp and perfidy I have only stayed until such a moment as my daughter and her youthful brother might more easily do without me.  You will cherish them both; of that I have no doubt.  Guide them, I beseech you, for the sake of your own glory and their well-being.  May your watchful care sustain them, while their mother, humbled and prostrate in a cloister, shall commend them to Him who pardons all.

After my departure, show some kindness to those who were my servants and faithful domestics, and deign to take back the estates and residences which served to support me in my frivolous grandeur, and maintain the celebrity that I deplore.

Adieu, Sire!  Think no more about me, lest such a feeling, to which my imagination might but all too readily lend itself, only beget links of sympathy in my heart which conscience and repentance would fain destroy.

If God call me to himself, young though yet I am, He will have granted my prayers; if He ordain me to live for a while longer in this desert of penitence, it will never compensate for the duration of my error, nor for the scandal of which I have been the cause.

Your subject from this time forth, Louise de la Valliere.

The King had not been expecting so desperate a resolve as this, nor did he feel inclined to hinder her from making it.  He left the Portuguese ambassador, who witnessed his agitation, and hastened to Madame de la Valliere’s, who had left her apartments in the castle at daybreak.  He shed tears, being kind of heart and convinced that a body so graceful and so delicate would never be able to resist the rigours and hardships of so terrible a life.

The Carmelite nuns of the Rue Saint Jacques loudly proclaimed this conversion, and in their vanity gladly received into their midst so modest and distinguished a victim, driven thither through sheer despair.