In the aftermath of Starkiller Poe isn't coping. He takes care of Finn when Finn wakes up, but he can't take care of himself. He's grounded till Leia is satisfied that he's okay (or until such a big emergency arises that she has no choice but to send him) and he spends every night either wandering the base until daylight, or having sex/drinking with strangers in bars.

Then Finn finds him one night, drunk/high off his ass, looking like he just got fucked in an alley (he did) and it hits him how bad Poe is. Finn makes it his personal duty to drag Poe from the depths that he's sunk to, and somehow he manages it.