Thank you all for your comments - it surprises me what people choose to read into a posting!
She will not live with me as she says she likes her freedom and she thinks I will nag her (she was always quite gross in keeping her room tidy) - which is probably true as I cannot live the way she does.
Just to clarify - I give her loads of help, she and the baby stay with me every weekend where she basically rests and I look after my grandson and I've a full time job too. Her partner says he cleans but when he turns round its a mess again. I don't know if he has just given up on it all or is just trying to sound like he is doing his bit. I can understand him just giving up, he's only young too, but it doesn't help.
I go up one or two evenings a week to see if she is ok and talk about what she has done and what she needs to do, but she probably sees it as nagging as there are things she needs to do that she ignores. I know she doesn't like talking to people but sometimes you just have to!
I take her washing and drying if she tells me its built up as it is sooo expensive for her to do with a prepayment meter, though when I went round this week there we about 10 bin bags of washing stacked in the hall that she'd moved out of her bedroom were she had hidden them, as she couldn't get in.
She's on pills (the same ones I've taken for the last 7 years after a breakdown caused by work, so I am well aware of the issues of MH). Her doc put the health visitor back in touch which took 4 weeks or more to happen after the request was put in and DD doesn't like her so wont open up anyway. She just tells her she is fine an the HV bogs off again another box ticked (and HV turned up the week after I had scrubbed the house so it probably didn't seem that bad).
I'm worried about contacting SS but also worried about not contacting them. She doesn't physically hurt the baby but its not a safe environment for him. I love my daughter very much and my grandson has saved her on so many levels, but she now has responsibilities.