I only communicate with my ex in writing. I send children out the door and don't make a big deal over the goodbyes - more like "oh, hey, Dad's here. Have fun! See you soon" and I have completely given up on co-parenting.
The best indication of future behavior is past behavior and bullies just don't change, no matter how much I want to believe they can.
I am glad you are safe. From now on - if there is a now on - I would have the girls sitting on the step waiting so that you can be safe in the house. I am so sorry that this happened to you.