I just don't clue in.

I'm not sure if it has something to do with me being too tired...But when I dream, like most dreams, it is quite absurd compared to reality. I can't seem to clue into the fact that I am dreaming, I even have dreams where I think about dreaming but I never attain lucidity. I see people that I havent seen since elementary school and I don't clue in, so I don't see how a reality check would work because the situation is different all the time...especially with the randomness dreams can create.

I have achieved lucidity on a few occasions but it is nothing like the stuff on these forums. It's like a little flash of lucidity and I think my mind just falls asleep again.

It's more like the state of your awareness and how you act in waking life.
I too have stuffs you mentioned and I don't get lucid nearly even half of them. :)

When you teach yourself to constantly question the world that surrounds you, it will bleed into your dreams too. Since we are very easily carried away by our dreamworld, you must be extra-aware.