Trying to coparent with someone I can't stand

We've been split up for 2 years and I still get angry every time I have to communicate with her. She's a good mom but makes constant passive aggressive comments about my parenting. Our 6 and 8 year olds can tell the tension is there. I want them to have a good relationship with both of us but it's hard when every conversation feels like a battle. Anyone figured out how to do this successfully?