Can we talk about this?
Leah is Loki’s guilty conscious, which means Leah knows that this Loki isn’t the kid Loki she loved. So the reason Leah is so angry at Loki is not because he abandoned her in the past, thereby betraying her, as I previously assumed, but because she knows what Loki did to kid Loki.
Leah’s need for revenge is to revenge not herself but kid Loki!
And really I can’t fault her for that.