what do you think of puppy love? I kept refusing a guy for 8 years!Help me!

Many classmates around me are going on with their puppy love. Is it really okay? Teachers and parents always teach us not to take up puppy love, because we have our school work. And they say as long as we fall in puppy love,we're gonna hit a slump...It seems true.and there are lots of examples, my friend's school scores fall down a lot due to puppy love.
But when i ask those puppy lovers, they think love is power, it can make them go up and up. But usually the truth is not like that. And i find out that most top students never take up puppy love, their lives revolve around school.
I know it must be different from western students'life, they always study but fall in love with others at the same time? What's your opinion on my words?

To be honest, there is a guy who hankered me for almost 8 years, but i kept refusing him. Do you think if i'm wrong? I'm afraid of hurting him as a matter of fact, but the eduaction of love affairs that teachers and parents give me forces me to refuse him. And i did that a lot of times. He seems really sad. And now he's already moved to another city, but he keeps writing to me. i dunno what i should do. I sometimes wanna accept him, because i don't wanna hurt him, but sometimes i don't wanna make myself be looked down upon by my parents and teachers and friends. And i don't wanna give up my school work, because i'm a top student. Am I inconsistent? Help me!