Saw your other post, and honestly you're kind of between a rock and a hard place. Unless you're ready to get married, the best chance is for one of you to find a job where the other is - however, your girlfriend probably won't be terribly employable in the UK until she has a few years of experience in her field, and while you could move your business over to the US, qualifying for a visa that way will probably require you to make lots of changes to how you work. (Not to mention a considerable lump sum of money to "invest" as a small business owner and the requirement that you hire a few Americans to work for you.)

Longer term, it may be possible to work something out, or to take advantage of whatever work experience she can get in the US. And, there is also the hope that things may change a bit on the immigration front in the US after the upcoming elections.
Cheers,
Bev