I would like to wear a Spanx-type body shaper, but I can't figure out a type that will work with my dress. In the past, I've had the kind that has legs through the thigh and goes up to the underwire of my bra. I was happy with it, but I can't figure out a way to make it work with my dress so I can go to the bathroom without taking my dress off. The dress has a corset-back, and I'd end up spending the entire night in the bathroom having to take my dress off to pull down the Spanx. And my venue only has one female bathroom, so even if I was willing to spend so much time in there, which I'm not, no one else would get to use it, which would cause a huge problem.
It is a strapless, tight dress, so nothing with straps will work, and I don't see anything that covers my crotch working. Those corset-style ones with boning are just so thick, I don't have the space in the dress, and the thickness defeats the purpose of wearing it.
The only things I can think of are
(A) Finding a legless one (I actually want the legs on them to keep my thighs from rubbing together. Or I guess I could just wear cut some tights/nylons into footless thigh highs for that purpose, as I can't wear regular tights/nylons I'm wearing thong sandals.) that has uncomfortable snaps at the crotch (if they even still make those). Though I probably wouldn't be able to snap them with my big dress on.
OR (B) Ruining a ~$60 body shaper by cutting a big hole in the crotch, and even then I'd still probably end up peeing on it.
Are there any midsection body shapers that works like Spanx (not boned, no hook and eyes or laces) that don't slip or roll down/up that you've tried? Or any other solution to this dilemma?
Note: I have tried bustiers, which never seem to offer any tummy control. And I'm not even wearing any kind of bra because I've been searching for many years, and I still l haven't found anything that fits. I'm about a 30L, but even if I find that size, I've never been happy enough with the fit, style, shape, and print (why bras have prints, I have yet to figure out) to keep one for $60-80. So I've just been wearing cheap 36DDDs, which fit terribly.