That is quite a large number of guys... But if it was a guy who slept with that many girls he would be considered a stud......with experience. Honestly if it bothers you then I wouldn't stick with her. Do you know the circumstances that go along with her sleeping w/ 30 guys? I'm assuming some of the were one night stands....and not all in relationships.

I always like to know how many people the guy I'm with slept with before me....but then again its hard to judge always from that. Some people start having sex at an early age. My number is low....cuz I started kinda late....

If it truly bothers you then don't do it. If it does but you can live with it....use a condom.