My 17-yr old daughter has moved in with her boyfriend, against my wishes. Now, she has petitioned the court for a custody change to his parents, & child support. Can they do this? How do I fight it?

The day she left, I called the police for their assistance in order to prevent her from leaving. At that time, the officer agreed that she was being so defiant, that it would be best if I allowed her to leave in order to avoid further conflict. I wanted to be certain that he agreed she was leaving of her own free will, I was not kicking her out, while NOT in agreement of it at the same time. He agreed. I then contacted social svcs for their assistance. They said they couldn't get involved unless I filed a Runaway report. If I did this, then my daughter would from that point on have a juvenile record, therefore, I didn't. Now, they are suing me for change of custody and child support when I have done nothing wrong... She had been asking me to allow her to be emancipated for over a month, which I did not agree to. She also bought her BF a wedding ring during the same time frame. Social Services and the police are in agreement with me, through several different consultations/visits (per my request) that I have a safe home, more than sufficient for while providing anything and everything a 17-yr old could want. (I have documentation of this from both police and ss) My daughter also stated to police during a visit when I called for their assistance, that she was safe and not in any danger, that she just wanted to leave and go to her boyfriends. She said since she was 17, she should be able to do so, therefore she was and did. What do I do? HOW - can I be sued for custody AND child support just because SHE wants to live with them. There is no cause... there were no issues... It's simply a matter of teenage love and defiance to parental rules and guidelines. HELP, please... court is THIS THURSDAY!