HEY NINETEEN--when did she start fuckin', in kindergarten?
That's a lot of mileage. The statistics are as follows: 20% of the sexually active adult population has herpes (HSV), and 70% of the sexually active population, I think between the ages of 17 and 35 (it seems to be a University course), has HPV (venereal warts, some strains of which are invisible to the naked eye), though this is an estimate; the Center for Disease Control doesn't yet require that cases of HPV be reported, but they want to do so soon because it's a growing epidemic, and HPV is linked to over 90% of all cervical cancers (of course, you don't have a cervix, but for thoroughness I thought I'd include that). The other good news is that gonorrhea is making a comeback, usually in the company of chlamydia. A person who has sex as rampantly as Hey Nineteen is not likely to visit the gynecologist regularly, I would think, in which case she could have any number of things and "just not know".
However, if she was willing to admit to that many partners, she might be willing to discuss the degree of sexual responsibility she's taken for herself; seems like you could pose some direct questions. Or drive her to the free med clinic. Bear in mind that HSV cannot be tested for--except by an expensive blood test--unless there is a current lesion.
Good luck.
--K