Accept the inevitable ~ go home by train after arranging for the car to be scrapped and then buy another car.
It's obviously the 'lectrics that are fooked and the cost of replacing them is prolly more than the car is worth. I know you are sentimentally attached to it but the value of the car is not much in £££££s, probably more like ££s. Time to cut your losses and p*ss off Mrs Nick by having a new (OK 'Used') car she doesn't know about.
Seriously I forget how old it is but it has done a fair few miles and another Focus will not cost much more than a couple of grand, if indeed you need another Focus. Something else might better suit your new life.
As for
Take it somewhere independent like... Ask Growler for advice...
Don't ask here - we'll rip the piss out of you.... 
I doubt that Growler has contacts in the Winchester area and from the sound of it there is no way it will be safe to drive it all the way from Hampshire to the Wirral ~ unless you want it to burst into flames and enable an insurance claim, which will prolly be disallowed now that the AA know that it is likely to "flame" on you.
