Why does Beatrice keep saying that Dante betrayed her?

In the
Purgatorio,31,
Beatrice says that Dante has betrayed her through being
attracted to other
women in the ten years since she has died. He has not been been faithful to

her beauty, which is goodness itself, but has been deluded by the false beauty in other
woman in
hell, such as Francesca (he fell down in front of her in a swoon,
moved by her story), whose
beauty...