Obsessive love
When you love someone so much you’ll follow them everywhere, even if they punch you in the face or tell you to go away. You're like a lovesick dog that won’t stop barking at the mailman.
'I saw you with him, and now I'm going to follow you everywhere.'
'I don't care if you're mad at me. I'll stay here until you forgive me.'
'You don't have to take me back, but I'll just stay here forever.'