Traveling alone in December - which country to visit?

Hi all!

I'm taking a week off in the third week of December and not sure where to go. I want to go to an inclusive resort but feel a little weird about going to one alone. I usually like to travel on trips where I'm constantly on the move, exploring and walking 10 miles a day! But for this trip I want to make it relaxing where I can chill on a beach, do light activities, and sleep in! Would also like to go to a destination that is fairly close to a nearby city or village that I could visit one day, like a day trip excursion. Any recommendations for good locations/resorts for solo travelers that won't break the bank?