Hey mobile. Ignore her texts about what she is doing. Could be a million reasons why, but its not your job anymore to be her chat buddy since she served you. You can be pleasant upbeat and nice when you are around her, but no reason to cheer on her GAL activities. Work on your own.
As for Mother's Day, just make sure your kids do something for her. Have them make her a card or something. You DONT do anything for her.
On the trip, why would you want to keep your kids from going? Is it a safety reason or a pride thing where you just dont want them to go without you? I know its tough and stinks to see her doing fun stuff without you, but do not use the kids as a tool to punish her. If she is taking your kids on a fun trip, by all means, let your kids have fun and a great experience. I know you say your D will be over by then, but do not count on it. Divorces can take a long long time. My W filed almost a year ago and we are still no closer to a D than someone who just got served a few weeks ago. And that is with ME trying to speed things up!
Yes, you are right. Things will probably get ugly once the D process starts. By their very nature Ds are adversarial and throw in child custody (like my D) and the sky is the limit as to how bad things can get. Just remember to keep your kids' best interest at heart. If you feel you having custody is what is best, then fight as hard as you can with no regard to how she feels. Again, just do not use the kids as a tool to punish.
Best of luck to you!
Me: 42 W: 32 Married 7 years together 8.5 S1: 7 S2:7 Bomb #1: 09-16-13 Recon #1: 11/13 A discovered 04-03-2014 W filed D 05-19-14 but never served me I filed D 12-02-2014 S 05-31-14 Divorced 5-19-16