Some of you may mock me for this ;P

But how do I overcome this recurring distaste in who the girl has kissed before etc? I am okay if it is a guy I respect, but she had a shitty BF, broke up, is literally one of the best friends I've had until I realized I liked who she is. I can't get over where those lips have been though, especially since I've never kissed a girl before.

It sounds pretty irrational. Can you guys spare some words of wisdom?