Why do homosexuals get so mad over the word "gay"?

When I think something is stupid, I sometimes call it "gay" and I see absolutely nothing wrong or mean about that but homosexuals get so worked up over it. Technically, gay doesn't mean two males involved sexually with each other, it actually means happy, people just alter words into modern day slang. If people can alter a word that means in happy into meaning homosexuals, then why can't I alter it to mean something is stupid or ridiculous? When I say something is gay, I mean it is very dumb or has no evidence behind it and is just a very stupid idea. I AM NOT referring to homosexuals when I call something gay. Why are they so ashamed of their sexual orientation anyway that they cringe when they hear the word that is just slang and has no meaning except "happy" behind it? If somebody said that was so "straight" then I could honestly care less...Or if somebody said that was so white (my skin color) then I wouldn't care...It's just a word, so get over it Chris Crocker and read a dictionary, get your facts straight before you make an idiot out of yourself. Besides, love is meant to be between a man and a woman otherwise, we wouldn't be able to reproduce and the human race wouldn't exist. If you are homosexual and reading this, please do not get offended, I am just expressing my point of view. Gay can mean anything (not just homosexual) since it is slang anyway.