My opinion about this is that it's really wrong to re-share another person's picture, especially if there's an added word or sentence shaming that person. That in itself is considered libelous or defamatory. It doesn't matter if it was deleted later on.
As for your sharing your pictures, nobody or nothing should prevent you from being "open" to other people on the net... especially when we just want to socialize or meet new people from other parts of the world. There's nothing wrong in this act... so the blame should not be put to the person who shared their photo but to the person who used the said photo to besmirch the other person's reputation.