Here is my suggestion. Stop going by her house and spending time with the girls. Yes, I know, you want to and feel you need to, but I promise that is having a lot to do with her cold attitude and trying to push you away. You need to set up a schedule for when you will see the kids, and if she refuses.......get legal help. Stay out of her house! When you pick up the kids, wait in the car till they are at the door, ready to leave. She resents you being there in the house.
Stop responding to her texting, unless she asks a direct question that needs answering. Then, use only two to three words to answer.
Yes, she most certainly is playing games. She wants what she can't have. She should think she can't have you! She should get a taste of what D really looks like.
Plan something ahead for weekends. You had a life before M, get one again.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!