Amy decides to be honest with herself – she's probably still in love with Karma. She probably always has been. But she's pretty fucking sure it's Karma's fault because Karma's never really been able to let go of her the way she should've when things became legit with Liam. (By that she means they still make out pretty regularly).
So yeah, she's angry. Yeah, she's jealous. Liam is around now like a barnacle on the bottom of a boat and it fucking hurts. And yeah, she gave them her blessing for Karma's birthday. But shouldn't she have known it meant 'I'm barely getting these words out of my mouth so please don't flaunt the fact that Liam has the piece of you that'll always be just out of my reach.'
10 years after the war & DH. The epilogue never happened. Harry is flooded with thoughts of a moment that has never left him. H/Hr implied. One shot.