You have two options. If you are unsure about petitioning for divorce but you want to draw a line under financial matters you can enter into a separation agreement.
This agreement details the agreement reached regarding finances and the family home. If you want to proceed with a divorce financial matters can be dealt with alongside divorce proceedings.
You may petition for divorce if your marriage has irretrievably broken down and based on either adultery, unreasonable behaviour, desertion, two years separation with consent or five years separation.