Self-fulfilling Prophecy

You know the kind of situation - you go to work thinking “I’m going to have a stinky day” and your negative attitude ends up making people so skeevy of you that you really do end up have a stinky day…

or you are so concerned that your wife will die in childbrith that you cross over to the dark side to save her, yet it is your crossing over to the dark side which actually breaks her heart and kills her… that sorta stuff

Would dopers care to share their experiences - either from their life, from history or from literature, of such self-fulfilling prophecies?

I’ve got an example. I had a coworker who kept kvetching about people not liking him. He’d act all nervous and weird when people would talk to him. He wouldn’t show up for work or he’d leave early, citing his feelings of alienation as an excuse. The sad truth was that people liked him just fine…until he started acting like this. There’s only so many times a person can hear “Ya’ll don’t like me!” before you start getting really irritated.