Daughter wants to move in with her mom

Hi guys,

So I have a 13 year old daughter, who lives 50/50 with me and her mom. Neither of us owe each other anything as for child support. She has told me a couple times in the past year that she wants to move in with her mom. I believe that her mom is behind a lot of this stuff and pushing her. Also this stuff usually only comes up when my daughter gets in trouble at my house and she is mad at me. The next thing you know I get a call from my ex asking me to let her come live with her because its obvious that we cant get along.

This past week my ex threatened to take me to court and get full custody of her if I don't let her come live with her. Well in MN at the age of 12 a child can make the decision which parent she wants to live with. Im sure the courts would of course have to listen to each side, and make that decision.

I don't want my daughter to resent me if I don't let her go, but at the same time it is not a wise decision. I don't know how many times in the last year my ex has called me up complaining about how she cant handle my daughter etc... She also lives in the small *** apt., which is just a mess inside. Looks like a hurricane went thru it, because she never cleans. She also has not idea how to budget money, has multiple collection companies after her has nothing for her name. She is also dating a guy that lives with her that has 5 kids with 4 different woman. Ive also seen on a couple of occasions where she treats those kids better than her own.

Meanwhile on my side. Im getting married in a couple months, own a house and all my cars, toys, and can budget money very well, just to start. Now no Im not the perfect dad, but really who is? Am I strict yes I am. I try to raise my daughter like I was raised with respect for others and how to get ready for your life. In regards to school work, I check her assignment daily, stay in touch with her teachers and make sure to schedule all before or after school events. Her mom doesn't care about any of that, and if she misses assignment's she don't make her turn them in.

My ex chooses to let my daughter do what ever she wants, with no consequences. If she gets money for a holiday her mom will let her spend it all. I will make her put at least half into a account and make her save the rest for something she really wants. My ex also claims she wants nothing from me for support or assistance to help her. I don't believe this for a second. She has always been money hungry.

Like I said there is so much to this its hard to type it all out, and Im sorry if its scattered about. I have a lot on my mind and confused, Im torn if I should let her go live with her mom, just to prove to her that things are not all they are cracked up to be. Curious as to your guys opinions and any suggestions