Partners DD sees me as a friend

[Mummy2MiaD]

I'm 21 and my partners daughter is 15
My partner had baby when he was in his teens, he split up with her mother before she was born but has always been a part of his daughters life.
I first met her when she was 13 and we've always got on great, I have a decent relationship with her mother too, as does my partner. Obviously with such a short age gap she'll never refer to me as a stepmum, which is fine with me as it's never really mattered.
Recently she's been spending a great deal of time at our house and she's been a little god send since our DD was born 6 months ago, she's a fantastic big sister and whenever she's here she'll always offer to watch her whilst I have a bath or get some cleaning done.
I suppose the problem is I'm not sure whether I'm overstepping the mark when it comes to conversations that we have. Her dad works away a lot and she comes round whilst he's away (no-one has a problem with this) but as it's just me and her she'll open up to me about numerous things.
Earlier tonight she told me last weekend she went out drinking and snogged a boy on a park. She also told me that her friends where smoking weed but she promised me that she's never done any drugs and then she asked me how old I was when I lost my virginity and asked what it was like. Now I told her that she shouldn't be drinking especially on the street and that there is no way she should be hanging around with people who are smoking drugs and told her that i didn't want to discuss my sexual relationships with her, she just laughed it off and called me a prude.
It's not the first time we've had conversations like that but she's never been quite so forthcoming before and I'm not sure whether we're overstepping the mark a bit.
A part of me wants to tell my partner about the drinking and her friends smoking weed but I know he'd go mad and then I'm scared she won't be able to trust me.
I'm just not sure how much I'm supposed to keep to myself, I never had a close relationship with my mum so there's no way I'd discuss those things with her, obviously DD is only 6 months so I've got no experience there either.
Is it a good thing that she can talk to me frankly or should I have a word with her or her mum/dad? I just feel as though I'm in a bit of a dilemma.

[2Retts]

If she truly feels she cannot discuss such things with either her mum or dad then you are her lifleline..a truly (and ridiculously) responsible position.

I would say, do not betray her trust. She will confide as long as she feels confident in you.

At the same time, do not condone the behaviour which you know will bring her harm. Tell her stories about you and your experiences which could remove her from her own experienes (IYKWIM).

[2Retts]

For the record, I think it is important to let your DP know that his DD is confiding in you and to let him know that you think it important not to betray her trust....just for the record.

[StabInTheDark]

It's a toughie!! I remember feeling in a similar predicament a few years ago when one of my DD's friends (aged about 14 at the time) came to me because she'd got drunk and had unprotected sex. She begged me not to tell her parents- after a massive moral dilemma on my part, in the end I sorted her out without telling them but gave her a stern talking to.

I do think it is a good thing she feels she can open up to you about this sort of thing- it means you can keep an eye on her in a way that most adults can't. Seeing as you get on okay with her mum, you could casually mention to her and your DP that she seems to be finding it easy to confide in you- but I wouldn't go into details, or she might end up shutting off from you.

xx