They didn't love her as they used to do, and at the end of the day Morgana Le Fay was left with nothing but the knowledge that it could have been different.
If Merlin had told her from the beginning that she wasn't alone, that he understood, that there was a better way it might have been different. He could have told her all manner of things and yet he left her stranded.
She would have saved them, if she could, so long ago, back when she never wanted to be queen and pain not hatred burned at every mindless execution. But Morgana is what they made her, Uther with his hatred, Merlin with his lies, and the others with the many wrongs they committed against magic, against her heart. And what they made is a monster, a villainous being that has come to represent everything Uther feared, and everything they hate. Morgana hates it too, even as Morgause whispers soothing condolences into her ear, because she's better than this, in every sense of the word. And deep inside the child Morgana is crying because she loves them still.