@Casey_03 I still think there are too many unknown factors in this proposed visit.
Can you ring, email her & get some more definitive intentions on what she plans to do?
I agree with you, as I have already said, you cannot be a tour guide. But, maybe she doesn't want you to be a tour guide. You know so little about her intentions but speculate the worst. Like I said, you know her. I do not.
Based on that alone, I suggest instead of wasting energy & time on whether you should feel insulted. Spend more on speaking/writing to her & finding out the facts.
Then you may be able to make an informed evaluation on whether or not it is appropriate for her to visit. But, do not burn bridges from some sense of 'righteousness indignation'. Particularly, when you have either not told us, or have not enquired about your Aunts intentions.
Being alone with a baby is not glamorous. It's hard bloody work. You will wonder in hindsight many time's after this child is born..."What did I do with my time before..."
If you imagine you will be in bed breastfeeding a contented little babe. Think again. Who is going to feed you, wash clothes, pay bill's... all of those little things start to encroach on your desire to sleep.
Many parents know the mind numbing, inescapable crying a baby can keep up while you try to soothe them. Checking if she/he is hungry, too hot, too cold, nappy, has wind & on it goes...
So, one Aunt has opted out because you think she thinks you have some expectation of using her as a baby sitter, and you wondered if you should be feeling insulted?
Now the other Aunt still wishes to visit and you think she thinks you are going to be a tour guide!
@Casey_03 give yourself a break. Find out what is her intentions. She may need some help translating something she is doing on your behalf! Or a myriad of other things that you might just find so helpful.
This precious little child deserves the best. So do you. Find out what is the best. Then, act accordingly.