First of all, can i just say CONGRATS on telling your parents. That is such a huge deal and i know how hard it can be to reach out to people (especially them) and tell them how you've been feeling. To me that shows that you are such a strong person who is willing to take action and try and help themselves get through how you are feeling.

As for your friend ... well it sounds to me like she is probably just overwhelemd/scared because she cares about you and doesn't want to see anything bad happen to you. If she's never really dealt with depression herself, it could make it difficult for her to really understand why you are dealing with things in the way you are, or why you act certain ways sometimes. Its no bodies fault, its just harder for her to try and help you i guess. Im sorry to hear that it is making a strain on your relationship, but if she is truly the good friend that she is, she will come back. Just give her a little time and space to herself, as she probably just needs it to regroup and figure things out for herself.

Hang in there,
Jacq