Fuck!

Does anyone have a good explanation why we use a word that means sexual intercourse for situations that are personally frustrating, troublesome or unpleasant? Is that how people think of sex? Isn't sex supposed to be fun, exciting and pleasurable? When in trouble we say Fuck! does it mean we wish to have sex instead? If it's a wish why isn't it taught as a polite thing to say to someone? Fuck! I don't know...

http://www.thinkaloo.com