My student's family won't let her study what she wants Yesterday I had a tearful encounter in office hours with the most avid participant in the math class I teach, in which she related the following situation.

She is an international student whose parents are well off by local standards but have made significant financial sacrifices for her to study abroad at the university where I work. Part of the plan was that she should have a scholarship, but it has recently been denied on the grounds her grades are not strong enough, and as a result she will have to switch to a nearby university in the fall. Part of why her grades aren't strong is because she is a very specifically focused student: professional mathematics is all she really wants to do with her life. She already knows. When she is able to do what she wants, she just studies math. She works extremely hard, but at end of the day she couldn't care less about her other courses and views the struggle to get good grades as a distraction from what's important to her. 

Her parents disagree that there is any future in math for her. They tell her it's not worth it and that she's bad at it. They're medical doctors in a country where teachers are treated poorly, viewed as people lacking the talent to do anything better, and are worried that a career in math would be both unremunerative and undignified—which might be the case in her home country, but my student also doesn't hope to return home. Nevertheless, for because her parents are footing the bill and because she's not willing to openly defy them, my student will finish a pure CS major when she enrolls in her new university, and won't be allowed to enroll in any future math courses during undergrad.

I watched her just crumble as she told me this, weeping and apologizing for it, unable to make eye contact. She's about to embark, without any choice in the matter, on a course that's going to make her miserable for years, if not longer, and moreover, from what I know of her, she is just the kind of person who should be in math.

I've told her there's nothing anyone can do to stop her from learning on her own, and that absolutely no instructor would refuse to let her sit in on whatever math course she wants, so that at most this will be a hiccup resulting in her getting a sort of bachelor's degree she doesn't really want at the expense of what she'd rather do, and that at the time she's financially independent, she can really study what she wants, but one could tell she's not completely buying this. She's devastated, and I can hardly blame her.

What can I (or anyone) do to help in this situation?
Some thoughts:


Suggest counseling.  They are much more likely to be able to help support her in expressing her goals to her parents, understanding their position, and perhaps in negotiating some sort of compromise with them.  Family relationship issues are likely to be a pretty common concern for college students, and a university counseling service will have had lots of experience with them.
Suggest talking to the financial aid office. They may be able to explore other options for funding if she decides to go on without her parents' financial support, though admittedly there may not be a lot of options for international students.
Talk to your contacts at the other university. See if you can connect her with someone who may be sympathetic to her situation, and who might be able to help her with some of the other things mentioned here.
Help her explore degree and course options. Is there some other degree offered by the institution that might represent a compromise between what she wants and what her parents are willing to pay for?  Are there ways for her to take more classes that she's interested in?
She needs to be able to succeed at things even when they don't interest her.  You write "She couldn't care less about her other courses and her grades".  Regardless of the degree she pursues, this is a recipe for disaster in US academia, where breadth is considered essential and degree requirements are designed accordingly, and overall GPA is widely used as a metric of success,  e.g. for graduate schools and jobs.

(I am guessing from your terminology that you are in the US.  If not, please correct me.)

She doesn't have to like all her courses, but she does have to be able to push through and do her best work even in those she dislikes.  That's a necessary academic and life skill, and as a faculty member you may be able to help her develop that skill.  Counseling services may also help with this, if she has some emotional resistance to get past.
She might find these courses more interesting if she gives them a chance. Even pure mathematicians can benefit greatly from knowledge about other fields, and you or other faculty members might be able to help her see connections with things that interest her more.