We have been warned since childhood that a day will come when we shall have to make some tough decisions. And I guess your time has come!
But after reading your post I feel you should stay put, as you could be the carrier of the virus to a 'less' affected part of Britian, especially when they haven't found a cure as yet! (Just my two cents!)
If I go back to the UK the risk is more for me being infected rather than me infecting, I have already spent 6 weeks in quarantine and would also go into quarantine in the UK on my return. As mentioned I would be in isolation in a rural area with no neighbours for a couple of miles.