There are 3 REALLY BAD REASONS to push for a separation
i )For revenge or punishment over emotional hurt. This is where you want to teach your partner a lesson so he will care about you more.
2. Not knowing how else to let your spouse know that you are unhappy.
3. Wanting to avoid facing the real underlying problems
A controlled separation works best when you and your spouse are clear about your reasons for separating. Do you really want a divorce, or do you want to interrupt a serious emotional drama in order to find new ways to improve and strengthen your marriage?
1. Time Limit: For example three to six months. (Note: It amy take at least 30 days to cool off.) Depending on your situation it might be best to decide not try to deal with any of the chronic marriage problems until after a period of time, such as one week, three weeks, a month--whatever each person needs. This is an excellent time for individual counseling to get yourself center more INISE yourself instead of circular arguments with your spouse in your head.
2. No attorney filing: Agree that neither of you will file for divorce during this time. This keeps the fear down and allows space for both people to look inside rather than over their shoulders.
3. Someone moves out: Decide who, when and where.
4. Split finances: Fair and just use and access.
5. Welfare of children: What is best for them with regular access to both parents
http://www.donelium.com/threebadreasons.html