My mother never took the kids to my dad's even after he had married the OW. He lived two hours away and never, ever did she meet him halfway.
In the long run, my brother and sister respected the fact that my dad made the effort to come get them, every other weekend, when he had to drive two hours to get them.
Yes, you will have to get used to seeing her at events like when the girls graduate from high school and so forth. But, you don't have to force yourself to be all gracious and accepting and helpful to them.
He's got you so worried about actually being the "b!tch" they have spewed about...you are going a million miles in the opposite direction to prove you aren't.
It's bull. The bottom line: He wants YOU to make his visitation easier for HIM. Parenting requires schedules changes and adjustments to accommodate your kids. This is HIS problem to figure out, not yours.
"You know, it's times like these when I realize what a superhero I am." Tony Stark/Iron Man
“Focus on what you can do, then do it with all your heart.” Lois Wilson