I'm biased...my family are in the Bridgewater area, and I spend a lot of time there every summer
Nice thing about the Southern Shore...about 1hr south of Halifax...a very pretty city, close to Peggy's Cove, a must see. A little further down the coast are small communities built along the ocean, my favorites are Lunnenberg and Mahone Bay. Along this stretch there is a large beach called Crescent Beach that I feel is just gorgeous...and very dog friendly.
I'm also heading out there again this summer so let me know where you decide to explore...maybe I'll find new areas of the province to love!