Lies, living in a fantasy

You must not lie.
You have to be all honest all time. No excuses...
Is it possibel?

I guess, all humans lie. Some more, some less. Some just fore fun, some to surviv.
I know people who create their life, based on lies. I schoul'nt judg them, but how come, lies is the only way to escape from reality? Small edited details, change the whole picture, and let the person creat a fake identity in the reality of lies. When did lie became reality?
I find it hard to lie. I'am not talking about small things like, 'Du you like this dress?', answering 'Oh yearh, It's great' when thinking it's ugly... I mean, real lies. The one you have to act in. Make up, and plan. I'am not good at it, I seem to forget, what I have lied about. Bitter sweet.
Lies is weapon, and they make wars. Like the one in Irak, based on denying lies. And hiding things from each other, make people feel forsaken.
I think Lies creats a reality, in whichs you can live, like a parelle world. You can keep yourself believing, but you can't hide. You know the truth, you can't deny to yourself.
I guess that's the hardest part.