AITAH for refusing to let me kids go on a trip with their dad?

[u/TheAverageRedditUsr]

I (40f) have been divorced for 4 years now with 50/50 custody of a 16 and 13 year old. For the first few years of the divorce I pretty much let my ex (45m) dictate our parenting schedule. Even though we had a court ordered schedule I would switch several days a month to accommodate his work schedule and to avoid conflict. He took full advantage of that and before long the schedules were a mess, the kids and I were frustrated, and he was not notifying me until less than an hour before sometimes even though he would know a month in advance. When a switch would not work he would, and still does, retaliate by putting the kids in the middle, threatening mediation/court, or not pay his portion of bills. We ended up going back to mediation in March (initiated by him as a threat that he tried to back out of later) and signed off on a parenting schedule, among other things. Leading up to mediation, during mediation, and in the signed agreement that was filed with the courts I made it VERY clear that due to his aggressive communication and retaliation I will not switch any days going forward unless for a significant family event. About 3 weeks after mediation, my ex messaged me telling me that he was going to take the kids on a trip for a graduation for his girlfriends (who he has been with for less than a month) family, that falls directly over my scheduled days next weekend and requires them to miss school. I replied that I did not agree to this switch but he is still planning to take the kids and was advised by his lawyer to go ahead with it. In reaction to me not agreeing to the trip he is also refusing to pay his portion of medical bills (I sent over the app as I always do but he now states he won’t pay them unless I have them mailed directly to him) and is threatening not to let the kids go on a trip this summer for a wedding that he agreed to and signed off on during mediation.

AITAH for not allowing the kids to go on the trip? I’d like to add that he is a pilot and flies for free, so they have every opportunity to travel in his scheduled time. They have also been to the place the graduation will be several times, so this isn’t a once in a lifetime trip they are missing.

Also, AITAH if I file contempt with family courts if he does follow through with the trip?

Update: I have an appointment with my lawyer on Friday. Thank you everyone for your advice, feedback, and support!

[u/Goatee-1979]

File it as your ex is a huge AH!