What Happened To My Friend On FB?

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So I had a friend on facebook.
I looked at my friend list and she wasnt there and her comments on my past photos werent there.
So I looked at my FB messages with her (the only trace of her on FB i can find) and her name is black instead of blue and you cant click on it. So I was trying to figure out if she deleted her account, and I looked at a friend of mine which we only have two mutual friends, (my missing friend and another person) and it still says 2 mutual friends but doesnt show her pic. What does this mean? Did she delete her profile or block me or what? And by the way there is no reason she would block me so does that mean she deleted her account?
Thanks guys