Teen's wishes and custody

Our 14 year old daughter is very emphatic that she wants to live with me if I divorce her mother. She has said "If I have to live with mum I will run away". She gets on very badly with my wife (interacts with her has little as possible) - so does her older sister (who barely talks to my wife, her mother, and does not even answer her phone calls) but she is 19 so there is no custody issue.

I also play a major role in her education (she is home educated and I do all the organising and paying for things, helping her when she has problems etc.).

I also have some evidence of emotional abuse against both daughters and myself, but I am worried that will be hard to prove. My older daughter is willing to give evidence.

If she wants custody (not sure she will given our daughter's wishes) will the above be sufficient to get me custody?

There is no such thing as custody and hasn’t been for years.

The wishes of the 14 year old would play a major part in any court decision if you can’t sort it out between yourselves.

My wife is refusing to discuss or negotiate anything. She seems to think I am not serious about divorcing and will come to my senses and stay with her so she is refusing any discussion or negotiation.

I have no idea how she will react once I make an application so I need to cover as many possiblities as possible.