I am not a hair stylist either, I'm a jewelry artist who happens to love long, healthy hair, so I really can't help you with what would be an average stylist's salary; however, I would assume how successful you are depends on the same things it does in any industry.  How good you are at what you do, how hard you continue to work at learning and improving your craft, and creating a product or service that is exceptional enough to build a loyal following are all tremendously important to anyone's success.  It may be that her heart just isn't in it, which is most important of all... none of the above is possible if you don't completely love what you do and make the commitment to being the best you can possibly be at whatever it is you choose to pursue.  A high level of success takes a lot of hard work and dedication in any industry.  If you really value her friendship, support and encourage her to do whatever it is she loves most... she'll treasure you for that!