Just be careful when you break up. The cops could come a'knockin. Also, she might do that just to 'help you out'. You know, so you don't kill yourself. Or, you could come home to find your gear gone, trashed by a caring and loving girlfriend who is too ignorant to open her mind, but is convinced she knows more than you do on the subject. And when you try to reason with her, it will be like talking to a cat. A couple of blinks here and there, but no real comprehension.
In fact, she will feel sad for you and tell everybody about your problem and how good of a girlfriend she is for caring enough to either throw out your gear, or call the cops on you. This way, all her friends will think you are some kind of drug addict, not to mention her parents. Boy, isn't that cool.
The best course of action, assuming you still want to be with this chick, is to acknowledge your wrongdoing. Tell her you have come to your senses and will never ever do gear again.
And then refuse to ever tell her anything again, and that includes where you go on the weekends. Sorry dude, but this shit from bitches pisses me off. It's either one of two things: 1) Bitches piss me off, or 2) I'm on fina, and bitches piss me off. If you guessed 1 or 2 you would be correct.