Heloise, though initially reluctant, eventually agreed to the marriage as well, and in 1118 gave birth to Abelard's son. They then returned to and were married in Paris. When Fulbert reneged on his deal and tried to make the marriage public, Abelard decided to remove Heloise from her uncle's house, and sent her to the convent at Argenteuil.  Her sister took her son when she entered the .
The Castration
Although Abelard continued to visit Heloise at the convent, the decision to take her away from Fulbert ultimately ended their romance. Believing that Abelard was trying to get out of the marriage by sending Heloise to the convent to become a nun, Fulbert sent his kinsmen after him. They snuck into Abelard's room at night and exacted their revenge by castrating him.
Though in later letters Abelard wrote that, in hindsight, his castration was an act of God's mercy -- allowing him to devote himself without distraction to God and to philosophy -- his initial reaction was much more human. Radice notes that in his autobiography, what he most vividly recalls "is the pain and horror, his urge to escape and hide from the noisy sympathy of [friends and pupils ... and] his humiliation and disgust at being a eunuch." (Radice, xxiii)
He was ultimately driven to seek shelter in the monastery of St. Denis, where he became a monk. Heloise, unwilling to repudiate their marriage, became a nun.

The Letters

We know of the romance of Abelard and Heloise through the letters they wrote to one another after they had taken their Holy Orders. Although both went on to become successful figures in the medieval Church, Heloise pined for their lost romance, complaining in her letters of her sexual frustration, her loneliness, and her desire for his company.
Eventually, their letters lose this one-sided passion altogether, after Abelard requests Heloise stop bringing it up, but they continue, both erudite and loving in their content, for many years.

Death and Burial

Abelard died in 1142, and Heloise followed him in 1163. They were buried together at the Oratory of the Paraclete, where they are said to remain together to this day. The Père Lachaise Cemetery, the largest cemetery in Paris, claims that they were reinterred there during the early 19th century, however, and have built a tomb to them as well (see photo below).

 
Their story continues to live on in popular imagination, and is retold in literature, in film, and in music to this day.

Sources

Hollister, C. Warren and Judith M. Bennett. Medieval Europe: A Short History (Tenth Edition). McGraw-Hill: New York, NY, 2006.
Radice, Betty (translator and editor) with revisions by M. T. Clanchy. The Letters of Abelard and Heloise. Penguin Books; Revised edition, 2004.


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