Long story but will keep as brief as possible. Planning a holiday with DS15 who I have 100% custody. Ex is a not someone that can easily get on with unless on his terms. Always picks fights and has ruined more than one holiday, especially Christmas and birthdays. They seem to trigger something and ex can't stand the happiness around these events.
Last holiday ex joined. It was a week away. I paid everything. Which I happily did to avoid drama. It was a complete disaster. Returned home after a few days it was so unbearable. So much so I have limited contact. And removed myself from any communication other than essential. In a word I'm done.
Planning another trip away DS accidentally mentioned it as ex planning a visit (visits once or twice a year). Rather than come after holiday away wants to join in for some of our holiday. AIBU to say no. We will be with my family and they don't like him.
I don't think I ABU. Just wanting to have some perspective because I'll be the worst person in the world if I say no.