Gotta say Broke, I agree with everyone else. Take the tickets and no invite to H. You may want to explain it is Mother's Day which is a special day between you and Ss, you do not want him there you just want time with your boys. I am sure there is better wording than that.
How did divorce care go last night?
Me 41 W 33 M 2013 Suspect A 11/15 Confirm A 1/16 She moved out 2/14/16 Stepson 13 Stepson 16