She's more interested in fishing than I am in landing on a grass runway.
Blasphemy!
I hope that's because you haven't gotten any instruction on grass yet, not because you're biased against grass runways. In fact, one "getaway" that is probably a bit too close to you to justify flying but that makes a GREAT stop on the way to (or from) somewhere is Lee Bottom Flying Field. Gaston's is another one. There are a LOT of these "must-go" places that are grass only. In fact, the multi-mentioned Amana Colonies airport is grass only.
Most of our getaways will be a weekend or maybe a little longer so somewhere that we don't have to spend more than 2-4 hours getting there is just about perfect. Any time of year is open, since I'm just trying to put together a list of future trips to consider when we can spare the money and have the time to go.
Okay, cool.
Unfortunately, since you don't own your own airplane, most places are going to charge you at least a 2 hour per day fee whether you fly it or not. So, you probably want something at least 200nm and up to about 450nm from Indy.
She refuses to camp (although she might go for a cabin....not sure, so go ahead with suggestions for that if you have them), which sucks for me.
Yeah, that does suck. I was thinking of... What's that state park in Kentucky with the airstrip? There's also Petit Jean in AR.
Any specific places up there that you recommend?
("Up there" being the Dells, KDLL)
If you're looking for a summer weekend at an outdoor water park, Noah's Ark (America's Largest Waterpark!) will keep you busy having fun. There's also some winter indoor water parks (Kalahari, Great Wolf) and a ski area (Christmas Mountain).
However, if you're looking for (downhill) skiing you're probably better off going to, in order of distance, C47 (Cascade Mountain), KAUW (Rib Mountain), KIMT (Iron Mountain), or something else. But they're probably all bigger than you'll find in Indiana.
She really has told me that she doesn't see the point in the "$100 Hamburger" runs, even if the food is more substantial. Granted, there are a lot of great restaurants I'd love to check out and hopefully she'll come around with time and a patient approach.
If you want to hook her, the two best airport restaurants in the midwest are Pilot Pete's at Schaumburg (06C) and Final Approach at Sheboygan (KSBM), both already mentioned. It certainly doesn't hurt to have a place to stop for a break and lunch on the way to/from your primary destination, though, and the Jet Room at KMSN is pretty good for that, very nice FBO too.