If there is a single fanfic you should read right now it's:
something old, something new (something borrowed, something blue) by coalitiongirl
“Of course.” Regina’s smile gets strained, as it always does when Killian comes up. Emma thinks of Regina in hell, (to be honest, you’re too good for Hook), and she doesn’t think Regina will ever adjust to Killian as everyone else has.
“This isn’t your house,” Killian says defiantly. “When the real Regina tells me to go–”
“She won’t. She’s trying to be noble ,” Future Regina says, and Regina clenches her jaw together. “She’d smile through your whole wedding if she thought it’d make Emma happy. I remember.”