He is trying to make you crazy. Get an attorney and go after him for fees also. Does he have an attorney? He has COBRA rights for up to 36 months after the divorce, but he has to pay for them.
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If he wants COBRA he can do so but he will have to pay. You are divorced. Secondly not sure if you are stating he has an attorney or not. In order to squash his action you need to hire an attorney. You have children involved and there are no do overs. Since he has his girlfriend in his house, you can ask that the children not be exposed to his affairs. Ask for supervised visits to protect these innocent children. Also he should be paying more than the amount you stated for child support. Ask for an increase ASAP.
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