I am separated since 1st Jan 2011. The first months we moved back and forth between an investment property and our matrimonial home. Since June 2011 my ex is moving into the matrimonal home every other tuesday for one week (to be with the kids). We are living in completly separate rooms and hardly see each other. He is paying me since the separation spousal support. Is this amount taxable, even if we still kind of live under the same address?