Turn the ultimatum back on her as sugggested here!
I was in the position a long time ago and unfortunately chose the girl and gave up something I loved at the time and wanted to follow to the commercial side(diving). I have regretted stopping ever since, have about £10k worth of gear lying around and she is now long gone!!!!
Luckily I now have someone very supportive who whenever I ask her something just tells me to get on with it
Dont give up or else you will be as p1ssed off as I was at the time and prob hate her for making you give up anyway!!!
J.