Because the guy at CAB was a bibbling idiot.
I told him the situation and he ranted on for 15 minutes about relate, regardless that I'd told him it was over, and we'd already been.
Then I reminded him I'd phoned for advice on benefits etc... so he spent 10 minutes telling me about rights to the house, which I know.
Then I asked about tax credits/benefits again and he said he had no idea. He took my details and told me he was sending me things in the post (I'd already told him not to as dh will intercept!) and phone me back with any information he could find out on what you can claim (ditto!)
I could have come to that conclusion myself...