CPAP is still the first line therapy for obstructive sleep apnea. Some people take to the mask like duck to water, more often though it is a bit of a struggle, sometimes for months.
Attitude is everything, or at least 99% of everything! If she really does not want to use the mask when she sleeps then she won't ever do it. For that remaining 1% this site has so many valuable tips and experiences I'm sure she can find a way to adjust the mask she has or get one that fits her better and allows her to sleep well.
You mentiond you've been reading the posts here. Surely you know that "feeling better" is a side benefit. The real benefit to successful treatment of apnea lies in eliminating the damage that is inflicted night after night on the body. Damage that is linked with high blood pressure, heart disease, diabetes, to name a few.
If you haven't already done so, please take a minute to watch this short flash video animation on Sleep Disordered Breathing and see how the damage is inflicted:
http://www.resmed.com/en-us/clinicians/understanding-sdb-english-640x380.swf
This video might be a good thing to show her, she may not be fully aware what she is trading for by not doing everything in her power to use the mask.
Blessings,
--pseudonym