I understand you can download 'wife' software for certain SatNavs?
It will come up with helpful prompts such as "We should have turned right at that turning", "I don't think we're going the right way", "I meant left - didn't you understand?" and if you don't follow the directions for 2 consecutive prompts, it will simply say "If you won't listen, you can do it yourself" and will then go into 'sulk' mode - tutting and sighing at random intervals.....
Once every lunar month it will go into 'PMT' mode and will be totally unpredictable...
You Know It Makes Sense!