So i've been thinking about how Delena is gonna happen and here are my ideas.

Damon is gonna use the dagger on Klaus in the season finale so he'll die. (end of season 2)
Then season 3 will start with Elena is the chuveiro looking at the picture od her and Damon at the Miss Mystic falls as tears stream down her face.
Obviously, Stefan will comfort her but it won't do any good, she'll push him away. Then she'll go to see Damon's body and i'm hoping her speech will be along these lines.

Elena:(as the tears stream down her face) Hi as she runs her fingers across his face. I'm running out of plans, am thinking and i err...can't do anything. Am so helpless, Damon. What am I gonna do...it just..hurts soo much. *kisses him* But still no response. She sobs.

Now back início Stefan is waiting for her.
Stefan:Hey.
Elena: Am really tired can I just go to bed?
Stefan: You can't do this Elena, you can't push me away like this.
Elena:Am not pushing you away Stefan i just..er..need time *takes deep breath* to process everything.
Stefan: Damon is gone, Elena. I know it hurts he was my brother but you can't do this to yourself. Can't you see Klaus is dead and it might not have gone the way you wanted it to but the biggest problem is gone.
Elena:Klaus wasn't my big problem, losing the person i *pauses* care about is. And this, is just beyond my control..i just can't. *Stefan comes close to hug her but she moves away and enters the house*

Later that night, we see Elena and Klaus' body she pulls the dagger out. Klaus is back to life and Damon is too cuz he used the dagger on Klaus and once he's back to life it makes sense that the vampire who used it on him comes back to life too.

(end of episode one season 3)