Thank you for the question. When Universal Credit look at this issue, they will still consider you a couple (you may be entitled to a carers element). The fact you stay in two separate rooms should not make a difference to the claim (in the positive or the negative). These parts of the UC are non-means tested so this may actually make no difference at all. However, if you find that this is unique situation and they do not make a decision in your favour, you will want to do a mandatory reconsideration with the DWP, however if your claim is still not accepted at this stage then I would highly advise taking it forward to a tribunal. If this is indeed a unique situation then you can have a "new" judgment made on it, if the judge believes that you should be awarded it then he can essentially make new law to support your claim.
I shall provide you with a helpful link that will assist you in finding a solicitor/representative near your local area. This will provide you with someone nearby your area who can assist you if required.
I hope this information proved helpful. You will find a local solicitor who deals with these matters on the law society webpage which is as follows;
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