I don't want to start a war -- so this is just in MY experience, but a girl that has been through that many guys has some psychological/emotional problem. Always the vast number of these multiple sex partners have been while under the influence and originate as a one-night stand.
I'm not here to pass judgement, but unless the psychological/emotional problem has been addressed, you will inherit some serious headaches (e.g., any variety of alcoholic, druggie, violent, cheater, liar, etc..).
And, no, you cannot "fix" her -- that requires professional help and/or the help of family and friends; and professionals don't sleep with their patients, and family and friends don't sleep with their loved ones (this, of course, does not include spouses -- but that's not your problem here).
So my advice, step back, take an honest assessment of the woman. Is she as I described. If so, be realistic about your situation and act accordingly.
Good luck bro -