Quit worrying about "maybe's". Armour up with information. Be prepared to calmly respond. Remember this: if she wants a separation she's quite welcome to leave! You aren't doing the "leaving" or "separating" so if she wants space she's quite welcome to find some and...your attitude? "Don't let the door hit your ass on the way out!". In other words, express your preference not to separate but open the door and tell her she's quite welcome to leave and it's unknown how long that door will remain unlocked or have a new hostess waiting on the other side to answer.
Live life! Have fun! It's about you and the kids. You ARE the family she's leaving and don't let her give you any grief. If she wants out then SHE leaves. Period!
Hope your trip goes well. Maybe you'll get smiled at by a cute stewardess. Always made my day brighter when travelling, anyway.
