In Northern Ireland, there is only one ground upon which you can obtain a divorce, and that is the irretrievable breakdown of your marriage, as evidenced by presenting one of the following five facts to the Court:
2. Unreasonable Behaviour
4. Two years separation with consent
5. Five years of separation
You can proceed on this fact if you can satisfy the Court that your spouse has been having a sexual relationship voluntarily with another party during the course of your marriage. If you resume cohabitation with him/her for a period more than six months after you discover their infidelity, then you could not proceed on this fact as you would be deemed to have condoned the adultery.
Depending on your income and assets, you may be entitled to legal aid to assist with the costs of the divorce, so always ask.