Illinois became a pure “no fault” state January 1, 2016. This means that you do not have to prove that your spouse did anything wrong to get divorced. Illinois has decided that all economic elements of a divorce such as property distribution, maintenance, and child parenting allocation must be determined “without regard to marital misconduct”.
In Illinois you can only use the grounds that the marriage is “irretrievably broken,” which means that you do not get along and the marriage cannot be repaired. The legal term is that “irreconcilable differences” have caused the irretrievable breakdown of the marriage and the court determines that efforts at reconciliation have failed or that future attempts at reconciliation would be impracticable and not in the best interest of the family.