I am being transferred back to London by my company after a year working in New York (have been on an intercompany transfer visa) Non negotiable

While ive been here ive been in a serious relationship with an american citizen. We eventually want to marry and settle in the US

How does this work in terms of process? An important factor is the employment one. He certainly couldn't support me financially at this stage and i would not be able to go for more than about a month without working in the US (so obviously would therefore not be able to return to the US on a permanent basis more than a month before i knew i could legally work out there).

Any help greatly appreciated
MollyCogs