Sorry but you are insane.
I literally hate getting the train from Stoke station (uni) (not far from Stafford) to London Euston (home) for two main reasons:
1) The Virgin train is incredibly expensive, even if you book tickets in advance with a railcard it will all add up to a lot over time.
2) The longer, cheaper train (London Northwestern) which you will have to end up taking as funds dry up takes AGES and stops about 20 times - nightmare!
Basically don't do it and just get accommodation in London.