seeing is believing?

In response to one of the earlier comments, i have chosen to deal with a question asked to me: Just because you think you see something, does that mean that it's really there? And my answer?: Well, no. Not necessarily.
We're all humans. (At least, I'm human, and i'm assuming that you are, too.) And humans like to make illusions for themselves, to try to make more sense of the world. Think about it. You must have conjured up an illusion without realizing it. In fact, you probably do it all the time. Take, for example, the way some people think about others. Most of it is probably just something we've made up. If you think of someone as a person with a perfect little family, and a perfect little house, and a perfect little life, you are definitely lying to yourself. Nobody has a perfect life. That's a fact. Trying to kid yourself into thinking that somebody's life is a walk through the park compared to yours is lying to yourself. Still, when you look at that person, that's what you see. And that's an illusion.
We have all sorts of illusions that we make for ourselves. Take safety, for example. that might be one of the biggest illusions there is. Does safety really exist? Is anyone ever really safe? we lock our doors and hide under our covers, and we feel safe, even though we're no safer than we would be without all of these precautions. But doing certain things make us feel more secure, so we keep doing them, even though in actuality we aren't really doing anything.
One of the strangest things that we do is this: when our illusions shatter, we just stand there, gasping in surprise, even though we're the ones who put them there in the first place. Why do think that is? think we should maybe try to change that? or stay forever as we are?