Divorce is the official ending of a marriage (before the death of either spouse).
The official proof of divorce is a Certificate of Divorce. If you have been married you need a Certificate of Divorce before marrying someone else.
The reasons why your marriage has ended are not taken into consideration by the court when granting a divorce. This is known as no-fault divorce. To obtain a divorce you just need to establish that your marriage has 'broken down irretrievably' and you can do that by showing that you and your spouse have been separated for 12 months. There are, consequently, few opportunities to oppose a divorce application.
If you have children under 18 then your divorce application also needs to show the court that proper arrangements have been made for them.
While it is common to think that a Divorce Application sorts out issues relating to property and children this is not the case. Property Settlements and Children issues are handled via separate paperwork and court hearings. A Divorce Application is really just the last bit of paperwork to do if you no longer want to be legally married.
There are a number of services that can help you deal with emotional issues involved in a relationship breakdown.