What does it mean when your ex still playing games when she has another Guy?

We're going through a separation/divorce and even though I only communicate to her only to pick up our daughter and her activities, schooling, etc., she's still playing games. At times, I would call her cell and even the one she got our daughter but get no answer. She has me on child support but I still get my daughter things besides that. I don't talk to due to her as a person and what I would really do to her. I think the Guy may have an influence on her as well but I think it's mostly her. I'm just tired of her using our daughter against me or putting her in the middle.