My question involves divorce in the State of: Michigan

My ex wife and I have been living apart for about 4 years. Due to life complications and my own character flaws, our divorce never even got started. I plan on starting it as soon as I have the money to file. There are no children involved, and there won't be any property disputes.
I have 2 questions.
1) Once the initial complaint is filed, are we considered to be married for the last 4 years, or is the Date of Separation considered to be when we actually split up and went our separate ways?
2) Can anyone give me a brief outline of step by step how to handle all of the paperwork ourselves? This won't be messy, as neither of us are fighting it or each other.

Any advice or links to helpful information would be GREATLY appreciated.