Can possession charges against me be dropped if the person that owned the drugs admits to having possession?

I, passenger and my best friend, driver, we're driving when we got pulled over. The officer smelled perfume and asked if there were any illegal drugs in the car. The driver said no and then he proceeded to ask if he could search the vehicle which then the driver said yes. The middle counsel contained plastic baggies a scale, empty cigarillo packets and a small jar that contained cannabis crumbs. There was also a bag of cannabis under 2 grams. The driver and I put everything into my blue purse. The officer searched the car and came back to me and the driver and ask who's blue purse it was. I owned up to it and said it was my purse because it was, so then he Mirandized me and asked me if I had any idea what he found in the purse. I said yes. I know what you found in my purse but it is not mine. He then asked me whose it was. I told him that I didn't know. He then asked the driver the same question as to who possessed the cannabis and the scale in the baggies belong to. She did not own up to it being hers so because it was in my possession. I was arrested and taken to jail. I received charges for possession of cannabinoid/synthetic cannabis of under 10 g and an unlawful possession of paraphernalia. If the driver comes forth and admits to having possession of the cannabis, will my charges be dropped? I do not smoke marijuana. If I have to take a drug test, I will pass it but she will not pass one because she does smoke marijuana. I didn't come forth and say it was hers at first because I didn't think I would have to considering she was my best friend and she knew it the items belonged to her but I have too much to lose. Also, given that I am supposed to ship off to basic training for the navy on November 13th. I assumed she would do the right thing but she failed to do so I have to do what I have to do, to put myself back on track.