In a divorce action for adultery, the following defenses may be made:

1. (1) procurement;
2. (2) connivance;
3. (3) the act has been expressly forgiven or impliedly forgiven by the voluntary cohabitation of the parties after knowledge of the act;
4. (4) the plaintiff is also guilty of adultery and without procurement or connivance of the defendant and not forgiven as provided in the defenses to adultery; or
5. (5) the action has not been commenced within two years after the discovery of the act by the plaintiff.