Combine strawberries and sugar in a pint glass. Cut lime in half. Slice one half into quarters; add quarters to strawberry mixture. Squeeze juice of other lime half into strawberry mixture; discard squeezed lime. With a muddler or wooden spoon, muddle strawberry mixture until well blended and sugar has dissolved. Add gin to glass; cover glass and shake well for 30 seconds. Pour strawberry mixture through a strainer evenly into 2 glasses. Add ice to each glass; top each glass with 1/4 cup soda water.