On the rest of that sneak peek...
Emma: I fought the darkness. You know, I do understand.
Regina: With all due respect but, you don’t. You went up to the precipice, but you got pulled back before it consumed you. I was consumed. And I have to live with that every day.
Emma: I can’t imagine how that feels.
Regina: It’s exhausting. I’m constantly at war with my instincts. Like with Hook, my first impulse was to rip his throat out because it’s not fair that he survives and Robin doesn’t.
So this made me think primarily three things:
1. The casual way she drops in that bit about wanting to rip out Hook’s throat (not just to kill him, but a violent, vivid description of how she would do it) makes it all the more disturbing, because she easily could’ve used anything else as an example (e.g. her immediate reaction to Marian’s return), but it seems that she wants Emma to know that this could still happen at any moment because she’s “constantly” at war with those instincts. It’s an implicit threat.
2. Regina, as usual, is being completely, utterly selfish and lacks all empathy when she casually dismisses Emma’s ordeal being the Dark One. Regina was never possessed by the Dark Curse. All of the evil was all her. Did Rumple encourage her? Yes, but he even said multiple times that it was ultimately up to her. She, with no voices in her head and no all-powerful dark magic constantly coursing through her (she had to work for years to cultivate her magic), continually chose to oppress, rape, and murder people purely for her own satisfaction and amusement.
Emma, on the other hand, did have to contend with all of that. And she didn’t “get pulled back”; she ultimately stopped herself, just like Hook did before he went through with the Dark Ones’ plan. Regina obviously can’t admit it, but Emma didn’t have it easier–she’s just far stronger than Regina.
3. They’re making more and more clear that Regina really doesn’t regret anything she’s done. At first, it sounds like she’s consumed with guilt: “I have to live with that every day[…] It’s exhausting.” But then you realize that no, she’s not talking about dealing with crushing guilt. She’s talking about how hard and tiring it is for her not to murder anyone in her path. She’s saying that she wishes she hadn’t been the Evil Queen not because of how many lives she stole and ruined, but because it would be easier for HER now that she’s decided it benefits her to appear to be good.
