Is she worried it's something like an STD or similar which she'd be embarrassed about or more that she is embarrassed about discussing her private bits or the thought they may think she's unclean or similar?
I'm with Ethel with thrush which could be from something as simple as wearing tight trousers or tights.
There are over the counter remedies though I'd take into account how long she has had it, how severe the symptoms are and any other conditions she may have such as diabetes or immune problems which would strongly suggest she should see her GP.
http://www.nhsdirect.nhs.uk/articles/article.a spx?articleId=87§ionId=1
Unless there is good reason they're not likely to look down there if the symptoms suggest something common like thrush. They are more likely to try a treatment and review if it doesn't clear up after a few days.
She could go to a walk in or GUM clinic if it's the particular GP she is worried about seeing, possibly even the practice nurse though she should check with the surgery if they can deal with this first.
She must have been through some kind of examinations if she has been through childbirth, had smears etc... so should know they have seen it all before.
She can also ask for a private consultation with a pharmacist and if she goes to a larger store like Boots is more likely to have women pharmacists available.