The Upper Tribunal takes the view that estrangement and separation are one and the same thing – they have ceased to regard themselves as an item. Estrangement does not require coldness or animosity – there are not degrees of separatation, either you are an item or you aren’t.

See CH/3777/2007 for the most recent decision to this effect, plus references to further cases where the same point is made.

So how can you have an ex-partner and not be estranged from them? The answer is where you are still very much an item and a couple in the every day sense of the word, but circumstamnces prevent you from being aggregated as a couple for means-testing – for example, where one of the couple is a long term hospital patient. This provision crops up all over the means-tested benefits, but it is probably least likely to apply in HB/CTB. In IS and Pension Credit especially, there could well be a claim from the member of the couple who is in care or receiving treatment – the capital value of the family home is ignored because they are not estranged from the person living there, even though they are not a couple in the social security sense.