Keep in mind, Emma doesn’t know these things that Hook did:
Take Milah from Rumple (and it was obvious that he didn’t care about adultery, because he knew she was married) and leave him fatherless.
Leave Bae to the ruthless Peter Pan, who he knew ripped out shadows and obviously didn’t care whether or not he died because Bae told him that he was like Rumple. (I mean, ONE INSULT and you throw the BOY to the crazy, shadow-ripping man/boy/probably-TL-of-Zelena.
Completely disregard going back for Emma when he got back to the EF because he wanted his ship (while Neal’s mind was solely focused on getting back to his family).
When he had the option of being a hero and reuniting a TL couple or committing ruthless murder, he chose the murder.
And I bet you 50000 cookies that she’ll never know ANY of that.
Did you see how much dancing around Milah they did in the finale??? She’ll never be brought up ever again. his tattoo of her name is probably gone too.