pimples on chest and back!

I have the same problem. Sadly I do not have a solution, I go shirtless, when ever I feel like it. It was very very hard at first, and I still sometimes feel very self conscious about it. I suggest going to the dermatologist to determine, what kind of acne it is, and then finding the best way to treat it. Remember to look for no less then 3 independent sources telling you the same thing. This must be much much harder for a girl, then a guy. Try not to think about it too much. And where your nice clothes anyways, chances are no one will say anything, and if they do, ask if they know a good treatment you can try. That will shut up most people.