Teen step daughter trouble

My step daughter is 16. She has sex with boys just to b in, but lies about it. She admitted that she wants to get me and her dad divorced. She blames me for the breakup with boyfriend, few months ago she got home late a few times, the last time we took her phone 4 punishment. She tells everyone it was me, her dad didnt know. She says love u baby to 4 boys, when i asked her bf bout it, im the reason they broke up, i thought they were broken up. Now she hates me and makes me bad where ever she goes. What can i do to show her i realy love her, and wants to help her not to mess her life up. As she didnt even do good in school. Plz help  

[margypops]

Its possible you need some help with the situation is there a school counselor or someone you can speak to ,once things get out of hand its best to seek some professional advice. She is a minor and she would be better being at home most nights not out with friends,I know teens are willful, but stopping of privileges may help you ,ie taking her phone which you already have done .If you know she is having sex is it possible to discuss protection and birth control with her .?