If I truly, truly, TRULY loved them, I would give up a job, friends and money. Almost anything in fact. Indeed, it might be better to list the things I would not give up:
1) My family. Sorry, but no dice there
2) My own values. Any girl who wants to change my most precious values (free-thinking, teetotalism and adherence to the law) does not appreciate me for who I truly am. So if your girlfriend or boyfriend wants you to kill someone for them, remember children, either say "no" or "do your own damn dirty work!"
3) My atheism. Sorry, but the only thing that's going to make me believe is evidence. I don't mind if my girlfriend is religious. Just so long as she doesn't try to "save my soul".
Apart from those three things, if you truly love them, and they truly love you, well then you should do anything to hang on to that relationship. Give up on drugs and alcohol, give up on having one-night stands, give up on having a lot of money if necessary.
Yes, giving up a job, giving up your house, giving up your friends and what's familiar to you to chase after someone you love might be insane and illogical. But love isn't logical - the evolutionary process isn't optimal and some of our feelings ARE crazy and make no sense from a logical or biological view point. So you can afford to be a bit crazy. It's the craziness that makes humanity so interesting.