^Honestly, I wish I could help you because I asked that question myself. Unfortunately, I found that even if you had read every single book DC had ever published, Infinite Crisis still wouldn't make sense.
I think you are confusing Infinite Crisis
with Final Crisis
. Soon to be followed by The Really Final Crisis of Infinite Proportions
Sadly, I wish I was because I read through Infinite Crisis and a bunch of the tie-ins expecting it to make sense at some point and it never did.
That and unbridled misandry of Amazons Attack have put me off DC forever.