Second home tax??

When I met my wife who at the time was a widow with an only child, it was decided that I would sell my house move into her house and I would renovate her property. I understood right from the beginning that I would have no claim on her property as in her will it would go to her daughter as per her fathers wishes should my wife die before me. As time went on we realised that I would be homeless if and when that time came, I would not present any problems for the wishes of her father. So 8 yrs ago I bought my own property which we use for the sake of using it, it is fully furnished and soley in my name and my only property. The local council insists it is a second home / holiday home and I pay full council tax, the problem I am going to have is if the Council decide to start charging double tax in 2024 because they believe it is a second /holiday home. So my question is if I register for the electoral roll at my address and change all my details, as in driving licence, car insurance, DWP pension and so on, almost as if I were single. Will I be breaking any law if I do all that and carry on living at my wife’s address as I should be allowed too? regardless if I have my property or not. I do stay at my property for a good number of weeks at a time and we both spend time there as it happens to be in a nice part of the SouthWest. I only bought the place to protect my future for when I might be on my own. Being a pensioner I simply could not afford to pay double tax on the house I struggle now and I would be reluctant to sell because of the circumstance I mention. Your thoughts and advice would be much appreciated.
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