Is it illegal to send text messages to curse maliciously?

If the degree of abuse is very serious, such as long-term abuse, fabricated facts abuse or violent abuse, you can file a criminal complaint with the public security organ, asking the public security organ to file an investigation, investigate the criminal responsibility of the perpetrator for the crime of insult and slander, and ask the perpetrator to compensate for the losses. This situation belongs to a criminal case, so it cannot be directly prosecuted in court, and it needs to be prosecuted in public security organs.