One way is to encourage a culture of healthy communication. In families and communities, we should promote open and honest conversations. If people are able to talk freely about their problems and concerns, there will be less room for blackmail - type situations to develop. Also, promoting positive role models who uphold good moral values can help shift the focus away from creating or spreading such negative stories.
First, we need to promote positive values. By emphasizing respect, equality, and privacy in our education and media, people will be less likely to come up with or spread such inappropriate stories. For example, schools can include ethics classes that teach students about the importance of respecting others' dignity.
We can avoid it by strengthening laws and regulations. Any form of blackmail, especially when it involves sexual aspects, should be severely punished. This will act as a deterrent. Also, media platforms should have strict content - screening policies to prevent the spread of such stories. If we create an environment where such stories are not tolerated, they will be less likely to exist.