1. That's not Sasuke's fault. You don't love someone just because they love you. Then it's not true love.
2. What? Who does Naruto love that hates him?
3. Once again, you don't love someone just because they love you. This is your everyday "Girl goes after douchebag and is surprised when he acts like a douchebag" scenario.
To answer this : I guess , Kishi does that because he finds it more relatable to real life ..and personally in my opinion I agree , In real life it's mostly like this !