Your daughter is probably being influenced by her peers since she is 16 and peer pressure has a pronounced effect at this age. You have been an active listener which is a step in the right direction. You must be careful though as to not say the incorrect things which she may feel threatened by and shut you off. I would suggest that she receive psychological counseling if it is deemed necessary. She may not feel comfortable speaking with you because you may judge her actions. She can openly discuss her feelings with a psychologist or a counselor in an open and accepting environment. The choice is yours what to do but this is a very touchy issue. Just continue to love your daughter no matter what choice she makes in life.
I hope that this has helped. If so, please ACCEPT. If you need further assistance, please let me know. Have a great day. Thank you.