The concept of separation is one where the body of law is much smaller compared to others, but in terms of your divorce is probably the most important. Two of the most important dates in any divorce (other than the date you are finally divorced) are your Date of Marriage and your Date of Separation.
These two dates have the ultimate effect on when the community estate commences and when it terminates. The Dissolution date (the date you are divorced) terminates your status as a married person, but separation could have taken place much earlier. In essence, separation occurs when the marriage is over. For this to happen, it only takes one spouse. I have a saying. It takes two to get married, but one to get divorced. As long as the spouse who wants to separate does two things, then separation occurs. Those things are 1. Have an irrevocable intent to dissolve the marriage; 2. Take some objective step demonstrating that intent.
The first criterion is subjective, namely forming the intent. The second is objective. The first prong means nothing unless you take some concrete step demonstrating this intent. The second criterion could be among other things: 1) setting up a separate bank account; 2) moving out of the bedroom; 3) moving out of the house; 4) having a family meeting announcing your intent to divorce- you get the picture. There are no bright lines as it comes to separation.
Courts decide these issues based on the circumstances present in each unique marriage. Hence a court can find that you can be separated while sleeping in the same bed. Conversely, a court could find that you were not separated if you were living in separate residences, but were filing joint tax returns. The Separation Date will have a significant impact on 1) the length of the marriage, hence potentially affecting the duration of spousal support; 2) the value of the community estate; 3) reimbursements; 4) how pensions and retirements are distributed and in what amounts.
This small issue can have an unlimited impact on which spouse ultimately gets what amount. Depending on the size of the estate and the dispute over the date, the difference could be millions. Therefore, if you intend to separate, make that intent clear and unmistakable. Put it in writing. File your Petition. Have it served. Be clear. Be unambiguous. Good Luck.