If you're Daphne, do you leave Donny for Niles the day of the wedding?
I know this might be an unpopular perspective but I probably wouldn't have gone for Niles, especially because how he treated Roz all those years... Always putting her down, the constant slut shaming, and just being an ass to her.
I've seen first hand over and over that if a guy treats a woman who they're not attracted to like shit, they will eventually do it to women they get with once the attraction starts to wear off.
Plus he had such messed up relationships with Maris and Mel. He just got married to Mel and appeared to be very in love with her but then is just willing to drop her when Daphne said she may have feelings for him.
That would just be too much risk to take in that particular moment. Maybe way before the wedding... but right before the start of it? I just couldn't do it.