When I was eleven, I met her.

I hated her.

When I was twelve, I called her names.

I hated her.

When I was thirteen, she punched me.

I hated her.

When I was fourteen, I hexed her.

I hated her.

When I was fifteen, I put a stop to her little club.

I hated her.

When I was sixteen, she was still beating me in all my classes.

I hated her.

When I was seventeen, she saved my life.

I hated her a bit less.

When I was eighteen, she forgave me.

I didn't hate her anymore.

When I was nineteen, I fell in love with her.

Who is she? I thought that was obvious...

Hermione. More precisely, Hermione Malfoy-Granger.