Its a shitty situation all around. I will admit some parents are fucktards and dont want to listen and be thick headed assholes. However I'm not saying your parents are "those" parents. When I started I was 21 and lived with my parents. I explained to my mom what I was about to do and assured her I had done ample research and that I was being safe about it. She said she really didnt like the idea and I told her just to trust what I said and that I was doing it regardless or their opinion. However I wasnt dissrespectful or rude about it. They accepted my decision and stayed out of my business. I was lucky.
Let me ask you this......How did you parents "find" your gear?? Either you left it wide open to be found or they were rooting through your shit looking for stuff. That was your first mistake. Then the next step is, Sooner or later they will find a syringe or they will be beating on the door while you are trying to inject yourself.
If it were me....I wouldnt get rid of the gear. I would let it blow over and grab myself some Cell Tech and a few other things that promise HUGE gains on the front label. And A big bag of super heavy weight gainer or some shit. Use my gear and lie about it. As previously said, theres no reason you cannot live with your parents and not have some privacy. But if they see you growing they will be digging through your shit when your not around. I promise they will.