Prophead,
First of all, everything 1in60 says is true... but will apply whether you train in the UK or the US, so I'd guess it's not totally relevant to your question. Even so, read what he says, and make sure you understand it before you go much further.....
As far as Visas are concerned, all the information is on the
US Embassy website. To study, you will need an M-1 Visa. Your girlfriend can stay with you on an M-2 Visa. But neither of you may work on these Visas. If you want to work as an instructor, your school will probably be able to advise on the correct procedure for applying for a temporary working Visa. If your girlfriend wants to work, she will also need a temporary working Visa, and may have to research this herself if her prospective employer isn't familiar with the procedures.
If, after more research into Visa, you do decide to "forget it and get real" as you put it, then don't rule out doing your training in the UK, either part-time or full-time, and possibly doing part of the training in the US.
FFF
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