Damon and Elena have grown closer over the summer. As we saw in the premiere, she's comfortable strolling on into his bedroom, and she expects him to share things with her -- like Andie's death -- so that she can help him deal.
Stefan's jealousy act is understandable, but does Elena really not see what's going on here? She keeps saying that she cares for them both, but loves only Stefan, yet is constantly drawn to Damon. But does she feel the same way?