Twitter stalker keeps finding me?

[Bahadur]

Must have hacked your ip or set up ip trojan on twitter or may have remotely installed a key logger on your PC.

In case of keylogger: Use a process viewer other than task manager to check for key logger as Antivirus cant find them. They are generally FUD (undiscoverable). Also they may have names like system or something unsuspicious when you view from process viewer. So check the publisher info too.

Safety from ip trojan: start using tor browser.

If these don't work maybe he knows your email ID and password or security questions

Its a long process, I know.This is all I can think of now. Maybe somebody else will come up with some shortcuts.