E.D.
I moved out when I was seventeen. I didn't move because of the relationship I have with my mom (which is good) but because I wanted to live as an adult. I wanted freedom through responsibility and was ready to take care of myself. My two girl children are just about to turn 3 and 4, so I don't have experience raising a teenager. I do have practice setting boundaries and it is one of the areas I am really working on right now.
I suggest you try to stop REacting. Begin setting boundaries that are from a place of love and self care. Loving action. For example:
-If you want to live by yourself, you will support yourself. This is NOT a punishment, but an opportunity for you to learn vital skills and self care. I will not patronize you or underestimate your abilities by treating you like a child. I am going to begin treating you as an adult.
-If you are disrespectful towards me, I will disengage from the conversation. I love you and support you, but I will not allow myself to be treated that way by ANYone.
-If you are disrespectful in my home or to your sister/step dad, you will leave my home. You may return when you are ready to act respectfully (which doesn't mean we have to agree on everything, but disagreements should be communicated through with love).
-If you move, I will really miss you. I really love and care about you. I worry about the decisions you are making because I've seen you get hurt by them. Here is my experience __________. I know you're going to decide to do what you're going to do, but I HOPE you will take the initiative to begin healing and taking care of yourself. I feel deeply sad at the fissure in our relationship and I am scared that you will become more hurt and wounded. I really want to help support you in learning how to heal and take good care of yourself. I am not going to enable your destructive decisions because I don't feel good when I do.
J., try to remember that REGARDLESS of what ANY of us do, our children may not follow the path we wish for them (even if that path is as simple as happiness). Now, that's not to say that we shouldn't do the best that we can, as loving, present Mothers. However, at some point, we have to let go. In this case, letting go is very, very scary. But holding on may be doing more damage than good.
I hear how much you love your daughter. I hope this all works out. In the meantime, I suggest you get as much support as possible, sleep regular hours, eat well and try to eat regularly and keep going to therapy. This will help you to be alright AND will set an example of self care. Good luck. I can relate to how much it hurts to watch a loved one make destructive decisions. I don't believe we get to change other peoples lives/decisions/behaviors. We do get to change our own. Big hugs, and lots of strength to you.