This? Is the exact moment in which Stiles finally gives up on Lydia. Once and for all. That’s an expression of utter, absolute defeat.
He’s been trying, so far. He’s been hoping.
But now, he knows he’ll never have her. That she’ll never love him back.
This, ladies and gentlemen, is the end of an era.
Ten years of being in love with someone unattainable.
Ten years of longing.
Ten years of aching.
Ten years of sweetness, of bitterness, of almost-conversations, of painstakingly chosen gifts.
This is when Stiles finally gives up.
And no matter what he says to Scott, later, about the 15-year plan - we all know he doesn’t mean it. His heart isn’t in it, anymore.
Because he has seen, once and for all, that the relationship Jackson and Lydia share isn’t just a casual one. So far, Stiles had hope, because it really seemed like Jackson was that shallow, that Jackson’s relationship with Lydia was that shallow.
But now, he sees that it is a love that even defies death.
Stiles can’t compete with that.
No one can.
But maybe, one day, someone will love him like that. The way he’s capable of loving them.