This question requires more details and explanation than this forum allows. The quick answer is that you will need to file a Motion to Reallocate Parental Rights and Responsibilities. Hopefully in your Dissolution / Separation Agreement, there is the Standard Relocation Notice language. If so, she will need to inform you and the Court before any move, at which time you can challenge the move as not being in the kids' best interests. At that time (or before) you can also seek to have either more structured parenting time or even move for Shared Parenting.
Regardless, you definitely need to consult with an attorney in your area.
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