What to make of this?

Let me start this with: I do not dislike my in-laws; I don't understand them...

Seriously, what would you make of this conversation?

The back story is that my sister-in-law and her two kids are flying from Los Angeles to visit my in-laws in Oklahoma in a few weeks. When they're in town, my husband, son, and I usually make the three-hour trip to see them in Oklahoma. This time, because their stay will be so short, it's supposed to be just me and my son making the drive during the middle week.

Me: Hey, I wanted to talk to you about SIL's and the kids' trip in a few weeks. We'd talked about us driving up there, but I was wondering if that will still work.

MIL: Well, we're moving in a few days so it'll depend on when we can have everything ready... So we're moving Monday, going out of town the weekend after for that wedding.... We get back, then it's one more day before they arrive...

Me: Okay. Well, we certainly don't want to be in the way. You can let me know if it won't work out... I was looking at our calendar and we have some things going on during that time. I just...

MIL: Can we just talk about it later? Like when they're already here.

Me: That's in two weeks. I have to make arrangements depending on what days we'll be away.

MIL: Okay, well, they get in at 11 pm on Wednesday SIL has to go to ___ for a baby shower and will be gone Friday night and Saturday night and I'm really looking forward to having the kids all to myself since I hardly get to see them... Then, they leave Tuesday.

Me: Well, we can come in on Sunday... er, maybe Monday and leave Tuesday.

MIL: Oh I don't know how worn out I'll be then.... It's not that we don't want you to come visit. We WANT you to visit us. You know you are ALWAYS WELCOME. I know SIL would really LIKE to see you and we would certainly LOVE to have you... You'll have a place to sleep for sure, but we may not be ready. Why don't you just call me when they're here already...

Me: All right.

AHHHHHH! For crying out loud, just TELL me what you want, Lady.

I talked to my husband about it, but asked that he not "intervene" this time. Every time he does in these types of situations, it tends to result in a complete emotional breakdown on the MIL end and she and I have to have a heart-to-heart and promise to "start over". We've "started over" eight times since I got engaged to her son... and I've only been married for two and a half years! Besides, I'm not due for another heart-to-heart with her until the Holidays...

I really just don't get her sometimes.

Would you stay or would you go?