I wonder if some of the appeal of books like Twilight, and every Harlequin romance novel ever written, is to experience all the drama of an unstable relationship, while at the same time being able to trust that the motives of the characters are pure.
I’m not excusing the red flags in Twilight, but I wonder if they’re acceptable only because they’re fiction and we know that Edward is the Good Guy. In real life, things are never so clear cut, or dramatic, or exciting. In real life, the screwed up guy hurts you - in fiction, he’s actually the hero, or the protagonist, and he fights against all odds to be worth your time. Perhaps playing with fire in the safety of a fantasy world isn’t so bad. And I’ve said it before - stable romances aren’t exactly thrilling fiction.