In a medium saucepan, combine the strawberries, sugar, and water. Heat to boiling, stirring occasionally, then reduce heat to a low boil and allow to cook for 20 minutes, or until a thick sauce forms. Remove from heat, then strain the sauce into a bowl, pressing down on the strawberries to release more juice. Discard the solids and refrigerate the sauce until cool.
In a large mixing bowl, combine the heavy whipping cream, sweetened condensed milk, and vanilla. Using a whisk attachment, whip together until the mixture is light and fluffy, around 5 minutes.
Spread ⅓ of the cream base into a loaf pan, then spoon ¼ cup of the strawberry sauce over the cream. Use a butter knife to swirl the strawberry sauce into the cream, then repeat layering with the cream and strawberry sauce. Cover with plastic wrap and place in the freezer for 4 hours, or until firm. Serve with remaining strawberry sauce, or fresh diced strawberries.