ds112496 you have been given some very sound advice I think, in particular stop blaming yourself, get a good lawyer and get what is legally yours in a formal family law agreement. (so he cannot come back and try and take it off you later).
Your daughter is at a 'volatile' age which if you ask a few parents you will get similar stories. Do not let her divide and conquer for her own purposes. No, the grass is not greener on his side of the fence and NO she should not be calling the shots. You should be. Print out the pages from face book where he tries to use your daughter as a spy. My husband is doing the same with my son!
My husband wanted to go down the lawyer path and I got some very nasty letters so I got a lawyer who fired back a couple of questions, mostly financial. Now two years later he wants to drop the lawyers and do it 'personally' but still will not ring me. I no longer trust him and will be using a lawyer for my own sake. My son, who is almost 20 and working and doing University too, texted him asking that he call me because he is really too busy and it is not fair on him (my son or I). We wait for a response.
I hope your husband is paying child maintenance, school expenses, food and utilities for you and your daughter and general upkeep of the home. If not, get to that lawyer and quickly, 2 months is too long to be holding everything up. After 17 years of marriage you are entitled to a say in what you get and what he gets.
Possibly your daughter, if it went to court could go and live with your husband. Just be careful you do not become an emotional football in their relationship because eventually she is going to do something he does not approve of and then it will be, "I want to go and live with Mum!" Then what do you do? All behaviours have consequences as you well know.
My in-laws are also treating me badly and blame me for packing up and moving on with my life.....after he had a 2 year affair and left me???
Keep you head up, and as nursenurse said, "This is business now." Try and separate the grief from the 'business' end of your feelings, a lawyer will help with this.
I know you want to know why why why, so did I. And I got a load of rubbish reasons, like he wanted to go to the cinemas more often....really? Well I never refused an outing once. In fact he had a very well constructed facade and used my money and time for his own purposes, till he embarked on porn, online sex-ting and texting and other disgusting stuff. Your husband may be ill or just being a complete tool. Either way you must protect yourself and your daughter.
Stand tall and strong,
Kind regards, blackemerald1