How would you feel if your spouse answer your phone calls and read your text messages.
How would you feel if your spouse were to check your email to see who you've been contacting, and what you've been saying? Or, to check your internet history to determine the internet sites you've been visiting? Or, to look over your texting history and cell phone records?
If you'd be okay with that, let's step it up a notch. How would you feel if your spouse were to install, without your knowledge, a GPS unit on your car to see where you've been? Or, a phone recorder on your cell phone or landline to hear what you're saying? Or, a keylogger program on your computer to know exactly what you're doing on your computer? Or, hire a private investigator to secretly follow you around and make video recordings of your activities?
If you're like most spouses, you would view my first set of investigative methods to be essentially benign, and revealing a possible paranoid streak in your sweetie. But you'd probably consider the second set to be a flagrant violation of your privacy. Does that pretty much sum up how you'd feel?