I can't rap my mind around it. How do you memorize all the chords? Unless I am looking at a book telling me what they are, I can't do it. I also can't change quickly for the life of me. Theres like a 5 second interval for me between chords. I am not a bad guitar player, I know some theory and I can play well but chords... damn. Help?
When you practice, don't start improvising, going crazy (although this is hard to resist sometimes), or playing songs, practice playing chords, changing from chord to chord and playing progressions.

You could try making a warm-up/practice routine.
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the more you practice them the more you'll start to memorize them it's pretty simple. I would say run through all of the variations of an A chord (ie. Am, A7, Adim...) until you have those down, and then it's a matter of moving those same positions up and down the neck. Just memorize how to form a certian chord with your hand then you can just find the root to switch chords.
Only way to learn chords permanantly is to learn them in context - play lots of simple chord-based songs and you'll soon pick up the ones you need, and the changes will become slicker. A lot of it's to do with building up muscle memory and for some people it takes longer to build up that memory than others.

Stick with it though! The good thing is that once something's properly learned, it'll stay learned.
Do it in super slow motion. Identify where you're making unneeded movements (ie. fingers move to high off the fretboard, fingers that should remain on the same fret move off the fretboard and then back into the same place, etc.). Just concentrate on going from two simple chords like Am to C. Then get a little more complex, like C to G. Eventually you'll make your way to something as crazy as the opening chords for the solo version of Bohemian Rhapsody (that intro took a month in itself for me to be able to stretch my hands that far in any kind of speed, and that 4669 chord still kills my hands, I usually just leave the 9 out and make it super easy...cause I'm cheap.).