I would keep short and simple. Cordial and Civil. If she brings it up, don't acknowledge it and leave as soon as you can. It doesn't matter and you are not her backup, you deserve to be treated with respect.
Keep up the prayer and being a better version of yourself..
I will keep you in my prayers my brother.
M: 34 W: 33 S: 7 S: 14 months BD: 6/2015 Separation: 6/2015 Back and Forth between Home and Moms