What the OP is ACTUALLY asking for is how to get his wife to STFU. Here's the real answer, and it will require actually moving the router this time, but will stop her dead in her tracks before she thinks to ask something like this again.

Bring in all of your tools, even ones you'd never need to do it. Spread out your drop cloth, put all your tools on it. Make sure you have a beer in hand at all times. Cut an unnecessary hole somewhere, just to start the process of annoying her. When you go to the attic or basement, whichever you need to use to run the necessary cat to move the router. Take a piece of scrap wood with you, and drill some holes in it just for the noise. Make this process last much longer than necessary. Take at least an hour nap, out of site in said basement or attic. Wake up, actually run your cable. Hopefully, by now, she's super annoyed by having to walk around your tarp covered with tools you're not using (I forgot to mention to place it in the most inconvenient location possible). Move the router to the new location, but do everything as slowly as humanly possible, making the biggest mess you can in the process. At this point, she should be bordering on furious because you've made a mess, been in the way, made noise, and taken forever. In the future, when she asks for something like this, remind her what a process it is, and she'll leave you alone and never bother you with requests like that again. I guarantee from personal experience that it works 75% of the time, all of the time. My girlfriend hasn't asked me to change any of our stuff since the great bedroom TV mounting episode 3 years ago, and we're both much happier for it.