First,
, I'm a mom and I know what we put ourselves through.
Now, without knowing everything, just what I've read by your posts, you're making this about you. It's not about you. This is her life and therefore, her choices and her consequences. As parents, we are only able to lay the groundwork, nudge and guide, lead by example and pray for their physical, mental and emotional wellbeing. Just because you are Christian and have brought your children up in the faith, does not make it written in stone that your children must follow your beliefs as well, once they are old enough to choose. Just because she chooses a different path, than what you had laid, weeded, put up handrails and dreamed about, does not mean you or she has done anything wrong. I'm living proof.
Besides a stubborn streak, I did not cause my parents many problems, unlike my sister. I was an honor student, involved in sports and student government and had earned some small scholarships. I didn't go out and party and naturally fell asleep by 9pm. My parents used to force me to go out, because I'd rather stay home and knit. At 18, I started dating a man 18 years my senior and began analyzing my own religous beliefs, compared to my parents Catholic beliefs that had been shoved up every orifice, as long as I can remember. My parents were sure this older man was taking advantage of me and would leave me used and abused. My parents wanted me to stop dating him and when I refused, they told me to move out. I moved out and married DH several months later. We'll be celebrating our 15th anniversary this year. As for being dominated by DH, oh please, I rule the roost.
My mom had visions of grandeur for my life. A high profile executive career, lots of traveling and devout god-fearing catholic. Instead, I work a well-paying job that I like, spend lots of time with my family, play with chickens and am a god-loving member of a nondenominational church. God has a plan for us, but it's our own choice on how we get there.
Just let her know you'll be there for her.