I also think you need to be prepared with what you will say and do if she says something like "Well, that may be what YOU have decided, but that's not the way it's going to happen!" Because now that you blew up their little love tryst, the two of them have probably spent the weekend preparing what SHE is going to tell YOU, and how SHE thinks it's all going to go down
The most important clue to me was this^^
1-They've been preparing, too.
2-They did NOT have the weekend they were expecting. HA!!
Thanks again Pup.
If anything else comes to you today, my ears are wide open.