Someone for troubled teen to talk to - self harming

[Madbess]

DD15 has been messaging a friend a lot the past few days - not a close friend AFAIK- but says this friend is self harming and Dd seems to be trying to help her.
Does anyone know who would be a good person for this girl to talk to - childline ? Samaritans ? I told DD she is being a good friend but I don't want her texting at all hours and feeling this girl really relies on her. Not wishing to sound callous but it is not one of her close friends so I made her switch her phone off last night to go to bed, she was very upset but agreed in the end.
I don't feel DD nor I should be too involved so would prefer to suggest an outside ( & indeed skilled ) counsellor.

What about the school nurse? Most secondary schools have school nurse drop ins, the school nurse can talk to her and help her access counselling if necessary.

We've just recently gone through this very same thing. An older girl at school was messaging my DS and sending pictures of her injuries and screen shots of suicide.org ... luckily we monitor pretty closely and found them straight away. We took it into school and showed the school nurse, who then informed the head of year. The girl is already seeing the school counsellor and her mum has been informed, so hopefully she is getting the help she needs now.

Thanks I have suggested the school nurse