I think June recognises the power in group mentality. Positive or negative, there is power in mass. Like when she was giving birth on her own, she drew strength from her experience with Hannah, Luke and Moira but equally from the indoctrination and chanting and routine of the Aunts and the Handmaids birth rituals.
Esther’s trauma is different to the handmaids’ apart from maybe Janine. Wasn’t janine raped before Gilead as well? June and the rest have been traumatised, no doubt, but they’re adults and had the privilege to grow up before Gilead so had a good grounding in a positive reality and can hope to recover from it if they escape and get the right help. Esther is a child and is a child that grew up being abused and raped and away from any love or hope. Her brain is wired differently from the majority of the other housemaids because trauma in children does that.
There is nothing that June can do for that child apart from give her purpose, give her the comfort of boundaries and rituals. I don’t mean traumatised children are beyond help in the real world at all, but at that farm in Gilead then the resources are limited.
I sort of think June is still taking the responsibility on herself by positioning herself as Aunt Lydia. Ultimately, the buck stops with her. How many of those handmaids have been able to absolve themselves of responsibility for killing as a group in Gilead because they tell themselves they did it because Aunt Lydia told them to? It’s true for Esther now too. Esther killed that man because June told her too. He needed to die because he’d have informed on them, but June took the power from Esther and gave her permission.
It was an amazing episode!