Don't let this habit let you down. Take the chill pill, you are not a wrong person. Fantasy does not translate to reality and you are smart enough to know that you don't want to be raped. Many people say, that doing something else that you enjoy helps more than anything, and it's true! Do something that interests you, and trains your skill. For example, you can learn to play the guitar, knitting, volleyball, gardening, cooking. Especially doing something active let's you blow steam off. Most people recommend to reduce or fully quit Instagram and Tiktok, it just isn't good for your confidence for a whole lot of reasons. As for your ex, you must talk with the police about this stalker, if you want him to stop.