CH/548/2007 considered this and decided that the regulation catches any former partner, not just the most recent one.
As to whether it is the same dwelling, the Painter case applies to ex partners who are now lodgers: the claimant occupied this room when she was part of a couple with the landlord, along with the rest of the house. She no longer occupies the rest of the house, but her reduced dwelling is still one that she and the ex partner occupied at that time.
