Jesus saying to forgive 7 times 7
King David was never allowed to forget. Something he had to live with and could not forget on his own even if allowed. The genealogical records show his son Solomon, "by the wife of Uriah."
Almost every JW knows someone that has been DF more than once. There are different ways of viewing such person, it depends. Sometimes a person has a problem and does not qualify to be JW. In that case, the person should just do the best they can and do not give up. That should not justify blatantly breaking all the rules and doing whatever the person wants. God is the final judge.