i think both their feelings are completely valid! imo, if you're in love with someone, you should love ALL of them, every version of them. But one thing i do wanna say is that i think it's fine if gyuha maybe prefers the old chayoung; aka the one he married and fell in love with, had children with throughout 8 YEARS, because now he's just gone. just like that. in a f**g day and there's literally nothing he can do to bring him back. And now, they're both left feeling insecure because of the unaddressed feelings between each other. but i have hope that if not for themselves, for their kids, they'll make it through.