Sorry for the throwaway but I need some help and hubby and I don't know what to do.

We have a 15-year-old daughter who has become a completely different person lately and I'm worried about her future. She has quit dance lessons which she has done for a decade, is avoiding her father and I, is constantly fighting with her sister who she shares a room with, has started acting like she's hiding things, and is always on edge. She recently cut her hair without permission (shaved one side of her head while staying at a friend's house). She has hair that goes about halfway down her back so you can imagine how angry we were when she came home with about half of it missing. She's since been grounded, which she is not handling well because she's been very mouthy recently too and it's affecting her sister, and has been banned from seeing that friend (for that and other reasons we'll get to in a minute).

We also think she's tried pot but we don't have any proof aside from one sweatshirt she wore home that smelled like she had at least been around it - a HUGE no-no in our house. We are a substance free family.

The main reason I'm worried is because of her friend, who I'll just call Anna for the sake of the post. My daughter and Anna have been friends since they met in fifth grade. I don't care for Anna's family (single, hippy-dippy mother, absentee dad, older brother who dropped out of college) but Anna had always been a smart, polite, academically focused girl. Despite her family, she has been a fantastic friend for our daughter and that's why we allow the two to hang out together, though we prefer to have Anna over to our house. The girls have gotten each other into mischief before, but nothing like this. Anna has had short hair for a few years now, but we never allowed our daughter to cut hers in case she ended up hating it. Cutting it without permission was the first thing the girls had done that was VERY against the rules.

But the biggest thing I'm worried about is what I found on my daughter's phone when she turned it in to my husband and I upon being grounded. She didn't want to give it up, trying to keep us away, but we got it from her and had her unlock it before sending her upstairs. Because of how she's been acting lately, my husband and I agreed to look through her phone.

Now, normally we don't do this. We respect our children's right to have personal space, especially because my husband comes from a toxic, suffocating family. When we had children we agreed to not rifle through our kid's things without reason but given our daughter's behavior, we agreed it was a good idea to see if we could figure out if something was wrong since she won't talk to either of us. We were worried someone was hurting her or maybe she had gotten into drinking or drugs. It's so much more complicated than that.

Anna and my daughter are "dating". They have texts going back as far as I can scroll (a few months, but it looks like this has been going on for a long time - possibly more than a year). My daughter and Anna have been spending hours talking about moving away together after high school, about my daughter going to Smith for college (which is many states away from where we live), and how ANNA'S MOTHER KNOWS but my daughter didn't want to tell us.

I feel so hurt. I don't know what to do. I want my daughter to have what I have - a family. I don't want her to be alone and I'm sick that she didn't tell me. She's never seemed interested in women or anyone so I don't understand why she wants to be with Anna. Could she be confused? Was I not a strong enough role model? Help!!