Rhiannon

From Wikipedia about the historical/mythological Rhiannon:

Rhiannon is a prominent figure in Welsh mythology, mother to the Demetian hero Pryderi and wife to Pwyll... Upon ascending the magical mound of Gorsedd Arberth, the Demetian king Pwyll witnesses the arrival of Rhiannon, appearing to them as a beautiful woman dressed in gold silk brocade and riding a shining white horse...

Under the advice of his noblemen, Pwyll and Rhiannon attempt to supply an heir to the kingdom and eventually a boy is born. However, on the night of his birth, he disappears while in the care of six of Rhiannon's ladies-in-waiting. To avoid the king's wrath, the ladies smear dog's blood onto a sleeping Rhiannon, claiming that she had committed infanticide and cannibalism through eating and "destroying" her child. Rhiannon is forced to do penance for her crime...

The Mabinogi do not present Rhiannon as anything other than human. Scholars of mythology have nevertheless speculated that Rhiannon may euhemerize* an earlier goddess of Celtic polytheism. Similar euhemerisms of pre-Christian deities can be found in other medieval Celtic literature, when Christian scribes and redactors may have felt uncomfortable writing about the powers of pagan gods...

According to Miranda Jane Green, "Rhiannon conforms to two archetypes of myth - a gracious, bountiful queen-goddess; and as the 'wronged wife', falsely accused of killing her son."