The author turned the end based on a simple misunderstanding ( that pill missing thing / i was bcz it dropped somewhere). Obviously after his own mother he wasn't in a stage to trust anyone and for that he was on edge , killed police officer who was saving him and even threatened Bumi and it all end up that way. But you know what? Since he was mentally unstable he couldn't recognise his own feelings for YBumi. In the last breath he only called Bumi.