How long is food actually good for in the refrigerator?

I go with the one week old rule of thumb, 3 days is way to early unless your home is a restaraunt, and my husband will eat things well into the third week if he brings things home from a restaraunt I am not allowed to toss it, (the only time he ever got severly mad at me is when I tossed his old take out food, so I leave it alone now). It's not like I am serving it, so he makes himself sick it is on him!