I seem to remember, somewhere I read, about 1/3 of disfellowshipped ones get reinstated. Some getting DF'd on a personal issue, get reinstated I think sincerely, just wanting to improve their life, but I don't think the act of DFing in reality was necessary or helpful for them.
People in all realms get into bad/tough spots and, eventually improve or move on. At least their circles, family and friends, don't shun, but remain with them, loving and encouraging them. The scourge of social shunning and aloneness doesn't help anyone.