Address not serviceable

We are a long term customer and have just moved to our new home. The postcode checker says our address can not be serviced. I have spoke to Customer Service and they have said the same. All the other properties in the street are serviceable. How can I convince Virgin to run the cable to my house? I have searched other broadband providers and they also say our hone isn't serviceable. My partner is disabled and is pretty much isolated at home and this is really her only contact with the outside world.