Don't advice her unless she allows you. If she wants to talk, listen to her and show that you care. Just tell her that you are always there if she wants to talk about any trouble she is facing.Let her take some time and tell you why she is depressed.
Meanwhile, take the family out to some movie or any place where she can enjoy herself. While she is around , try talking to some other person your own story - anything that you were depressed about, and how you did overcome it, making sure that your daughter is hearing the conversation. Call her friends/ relatives or throw a surprise party and make sure she is involved. She may refuse to join initially, but will come around soon.. All the best !