Hi Debra,
Please make sure that your daugher understands that her diagnosis is not a death sentence, and is necessary to keep her as health as possible. Now that she is diagnosed, she can receive the specialty care and treatments that will enable her to achieve all of her goals and dreams. There are many CF specific treatments to help her, and hopefully, more on the way. The treatments she will be prescribed are managable, and will interefere with her daily life far less than a serious sickness caused by ignoring treatment.
Obviously, since she has lived to 17 without any real treatment, she is a mild case. She may have had episodes of feeling lousy that went undertreated or mis-diagnosed - now that she has been correctly diagnosed, she can be treated correctly and should feel a lot better. Most of her treatments will focus on prevention and minimization of inflamation and infection - she will have a lot of days where she will think to herself "I feel fine, why do I have to spend all this time taking my meds, etc." Please stress the importance of maintaining lung health - once serious deterioration occurs, there is only so much treatments can do to bring it back.
Please do not feel that her diagnosis puts limits on her. Encourage her to go to college, work, play, exercise, and do virtually everything she ever wanted to do before her dx. Of course, if some of these desires included smoking, drinking excessively, and other generally unhealthy behaviors, please make sure she understands that because of her CF, these activities could be extremely harmful - moreso for her than others. She will probably have a lot of trouble adapting to life with cf - just remember - she doesn't have to like it, or even be accepting of it... however, she does have to take care of herself and comply with her treatments... not doing so will hurt her in the long run. And remember... we're all in it for the long run.
Chris
25 w/cf