I would definitely take what you have posted here and tell her doctor. There's something else going on here. Pretending everything is fine and then lying to her friends about her "horribl"e family just isn't normal.
Ok, this is sounding eerily similar to some issues my Son is having (withdrawl from things he once loved, telling other people that I kicked him out (I didn't), feeling worthless, etc.).....Do you know WHERE your daughter was cutting?
The reason I ask is my son mentioned once to me that he used to cut, but says since he has this GF he doesn't anymore, but I was just floored....I figured if he was cutting I would see it...it would be obvious, right? I mean he goes around shirtless all the time and I never saw any marks on his arms or torso....never on his feet (he goes barefoot alot too)...so I'm just wondering if you know where your daughter cut herself?
We just recently started counseling too BTW....not sure if I'll be able to get him on Meds, but am exploring that option as well.
Not all cutting is that obvious. Some kids do it on their upper thighs, or they'll cut superficially so that it heals in a matter of days. It's good that you are taking it seriously, though!
Unfortunately this weekend I ended up having to take my son to the ER for a Psych eval because he got so upset over me cutting off his cell phone that he took a lighter to his arm, and burned a spot on it (not more than 1st or 2nd degree...but still!).