Question: Would trying to clarify Sunday plans constitue pressure on him?

I would probably plan on using the sitter and going to the party. Is this not a party you can take your boys too? But, leave the option open if your H suddenly invites you. Cover all your bases without involving him, and expect the worst-case, which is he goes to a party without you.

BTW, good job on the no-call. Assume the best, which is what it sounds like happened. So, what's the best case scenario about him not inviting you to a Sunday party?

FF