The circumstances surrounding the failed negotiations to wed Robert, a weak and incapable ruler, to Eudocia are unclear, but George Akropolites states that the arrangement was blocked on religious grounds by the Orthodox Patriarch Manuel Sarentos: Robert's sister Marie de Courtenay was married to Emperor Theodore I Laskaris.

Accordingly, Robert, already Theodore's brother-in-law, could not also be his son-in-law.

Regardless, Robert had promised again to marry Eudocia but soon repudiated this engagement, and in 1227 (according to William of Tyre Continuator) secretly marries the Lady of Neuville, already the fiancée of a Burgundian gentleman.

Both the new wife of the Emperor and her mother are placed in a manor house owned by Robert.

The unnamed Burgundian gentleman somehow finds out and reportedly organizes a conspiracy against Robert and his new wife.

The knights of Constantinople partaking in the conspiracy proceed to capture the Empress and her mother.

The lips and nostrils of both women are cut off and then thrown to sea.

Robert flees Constantinople following the attack, seeking the assistance of Pope Gregory IX in reestablishing his authority.