I remember one dream I had where H followed me around all day, laughing and pointing at me. It was horrible.
Sigh. Helping him move out. I actually chose to keep the kids busy when he packed his stuff up, so they weren't too affected by it. I think your balance of taking the kids out and then offering any assistance when you return is good. Think of things he might not think of (cell phone charger, Advil, stuff like that) and tuck it in without a word.
Bottom line for me is: I wish H would be happy with me, but if that's not possible, I am going to support what makes him happy because I love him. Obviously I won't dress him to go out with OW, but you know what I mean.
Saturday will be hard, I'll be thinking of you.
Yoyo is right, stay neutral, don't say things like "I'll miss you". If you need to say something say "Have a good night" and stay neutral.