Order tickets to this event in Rehoboth:
https://www.eventbrite.com/e/schellville-2022-enchanted-winter-celebration-registration-419883592127
It's free but you have to get tickets in advance. It's a lot of fun. Maybe avoid it on Black Friday as it is right behind the outlets but could be fun on Saturday.
The OC Festival of Lights is usually open by that weekend. Again, look into tickets in advance because the tickets lines can be long. And there is a craft show at the convention center:
https://www.ococean.com/events
I think you will find enough open to fill a weekend. If nothing else, there are movies, bowling, shopping--all the things you could do here. My parents live there so we go a lot and never run out of things to do. Maybe book a hotel with an indoor pool!