Paranosis

A paranoid psychosis.
A supercharged experience usually induced as a random reaction to drugs, mental or emotional instability or a combination thereof.

When a person is constantly eavesdropping your conversations (usually a significant other) because they have just done something sneaky and are afraid that you are going to find out from your friends, or they are worried that you are on some sneaky business. Usually people who are paranosy have done a lot of dirt in the past so they are projecting that on to others, or they have had a lot of dirt done to them and they are being hyper-vigilant. For example, they could be in the other room and hear you speaking on the phone and all of a sudden they are right next to you on the couch asking “who is that?” and nonchalantly “oh, what did they have to say?”. Or if you get a text they will try to position themselves so they can see what you are texting without actually grabbing your phone out of your hands to read it. Although there have been extreme cases of phone snatching, or sneak reading.