Originally Posted by
Asdfywea
Ok, here goes my theory
It's not the girl she's kissing that will die.
Ellie will get in a fight with Joel soon after the start of the game, having finally found out that Joel lied to her at the end of the first game (you get the sense she knew then, but still, she finds out for sure here), and one of them storms off.
Then, if Ellie stormed off, she gets caught by the cultists, Joel arrives to save her only to die in her hands, without any time for good byes or last words, OR if Joel stormed off, she finds the cultists killing him before she can save him.
Remember the trailer with Ellie playing the guitar? I'm thinking that's after she followed and kill the ones that killed Joel, and he's not really there, she's just talking to herself out of the grief that the last words she actually had with Joel where in a fight.
That's my theory for now at least.