An unbroken discrete symmetry, analogous to G-parity in QCD, exists in standard model extensions with vector-like coupling of electroweak SU(2) to ``hidden sector'' fermions that are confined by a strong gauge force. For a general SU(2) representation of the hidden sector fermions, the lightest G-parity odd particle is always the neutral part of a weak triplet and a potential dark matter candidate. Assuming a mass splitting between the neutral and charged parts of around 10 MeV, there exists a resonance, a dark matter-nucleus bound state, to mediate a novel dark matter-nucleus scattering. The scattering cross section becomes highly element dependent, has increased modulation and as a result can explain the DAMA/LIBRA results whilst not being in conflict with other direct detection experiments.