Dear Scarlett, don't be too hard on the witness at your work, they are a victim also.
Your whole world has been tipped upside down just now and not getting a good sleep is normal in such a situation, in time you will feel peace and contentment. My best advice for now is don't fall into a habit of drinking a lot, it's easy to get into and hard to get out and with regard to new friends there are a lot of nice people out there, but vet them carefully, look for people with goals and ambitions and avoid people that use drugs.
Always, always be kind and polite to your parents, not only do they deserve your respect but they are victims also and they will soften in time.
RB