Did I mention that I am freaking out? Job talk is nearing completion, though.
I've decided to tell my collaborator what is going on when we talk this afternoon. It's only fair that he knows what's going on. I just hope he doesn't say anything to anyone else, because this would really open a whole can of worms!
eta: I told my collaborator and he said "great! congratulations! good luck!" and that he agreed that if I get a job AND we get funding that we can still collaborate long-distance. I'm feeling good about that- I don't know why I thought he might be annoyed that I am trying to leave. Also- my job talk is almost finished (I did a dry run and it was about 36 minutes). I have a LOT left on the other talks AND I need to work on this proposal- and be sure to mention it at the interviews, too!