Contesting a separation agreement

In the beginning of 2012 my husband and I decided to get divorced. In NC we have to be separated for one year to get divorced so we made a separation agreement. At that point I didn’t contest the terms of it and we both signed and had it notorized. In the separation agreement there is clause stating that the kids cannot be moved to a place more than 20 miles away without my ex husband approval. Also, there is another clause stipulating the minimun visitations day by week that my ex husband has the rights to have. I wasn’t working at that time so he paid me an alimony for 2 months until i find a job. Now, I got an offer to a better job (better salary, better position, bettet benefits) in a city 85 miles away from where we live. I went to talk with my ex husband and he didn’t oppose to it but 3 days later he came to talk with me saying that he won’t authorize the kids move. That “meeting” happened at my work (we work on the same company) and he was extremely harsh with me, threatening me to go to court, he was disrespectful with me, called me names and used foul language. I got very stressed and shaked psychologically. I couldn’t stay at work and I had to go home.
So what it can be done now? Can I contest the separation agreement? I can’t stay working on the same company that he works and I won’t turn down such a good job offer. I need to provide to my kids and the child support that he pays it is not enough to pay all the expenses. I am afraid what he can do. I proposed to have the kids visit him every other weekend and the city is just 1 hour and 20 minutes from where he lives. And I am not planning to move until the kids finish the school year. I’ll be commuting every day until the kids finish the school year but I can’t do this for the rest of my life. What are my options?

You need to file an action for child custody. If he will not agree to let you move with the children, you will need to let the court decide.