Complex sentence: A no-fault divorce allows a person to obtain a divorce easily as the parties no longer want to be married and it is obtained because one of the spouses testifies that the marriage is irretrievably broken (your state might not use irretrievably).
Split into simpler sentences: A no-fault divorce allows a person to get a divorce just because the parties no longer want to be married. In a no-fault divorce, a person testifies that their marriage is irretrievably broken (your state might not use irretrievably).