My 15 year old daughter acts the same way. I think they understand more than we give them credit for. I mostly think not talking is their way of showing us they feel robbed of what their older siblings got. They feel somehow that they have missed out on things. The best thing you can do is to keep positive, be consistent, show stability and give her a feeling of a safe stable environment. If you can, somehow get her a counselor. I would tell my lawyer that I want a counselor for her and her mom refuses. I would guess that your lawyer can come up with any number of legal avenues to force this. I am sure every kind of road block can be thrown up until your wife agrees to this. I would tell your lawyer you will drag this divorce out for years if need be unless your wife agrees to this.
Continue doing what is right for your daughter. Show that she comes first above everything else.
Twisting on Life's Rope Me53 W53 M20 D21 D19 D16 BD 2-2013 D final 1-2015 _________________________ "Dream about tomorrow, Live for today, Learn from yesterday"