Probably my least favorite verbal tic is when people use the word "should" as a passive-aggressive way of saying "must." As in, "You should read this book/see this movie/try this diet."
I always want to say, "Why should I? What about this product makes you think it would be perfect for me? Or what is it about me that you think needs fixing? Or are you just hoping for someone else to validate your life choices?"
I don't say those things, of course, because it would be tremendously rude. But it is equally rude, in my opinion, is telling someone they "should" do something. I know it's a colloquial short-cut but I loathe it.
"Should" is a terrible word. It conveys guilt. "I should start working out again." "I should call my mother." "I should write X number of words a day."
Should sucks. Purge the word from your vocabulary. If you find yourself thinking, "I should do X," then immediately drop whatever you are doing and go and do it, or at least schedule a time when you will do X--and then do it.
You'll feel better without the weight of those shoulds on your conscience.