I don't think F1 is a good idea,if INS find you never attend class, you'll be deported from USA.By the way,why you waste money if you don't want to study English( maybe it is unnecessary)The best way is that:marry your GF before OPT expire,& file I-539 form to apply H4,usually this need 3-6 months, but don't worry, during peeding period your status is legal.