"I really like her, you know,"
"I know you do,"
"Do you think she likes me? Deep inside? I'm starting to doubt it now,"
"I… she's scared James. I know she likes it when you court her. It's flattering, you know? It feels good to have someone always around you, telling you how beautiful you are or how incredibly smart or funny you are. And to have the James Potter, liking you? It's even better. You're the guy every boy wants to be, the guy every girl wants to date. And having you liking her… all she can do is to feel flattered. Because really, what are odds of the most popular boy in school liking you? That of all the pretty girls in school, he chooses you? She's scared, James, because she is starting to like you. Getting to know you, spend time with you and laugh with you has got her scared. Because she knows just how she could really fall in love with you; how easy it would be to fall head over heels for you, just like every other girl here in Hogwarts. And that would ruin it all, wouldn't it? She thinks once you know she likes you, it will all be over; she thinks you only like her because she doesn't, unlike everybody else. She thinks she's a challenge for you, a price. She fears that once she admits it, you'll ditch her and go back to some blonde chick in Hufflepuff, having finished the competition. And I can't say I think you would, sometimes.
"Even if you do love her, what tells you that you won't love any other girl the next day? How can you guarantee you'll still be in love with her after a week? I just… I think she likes you, too. And now, I'm afraid. She's my best friend, and has been for almost seven years. I love her, and have loved her longer than you have. But if she loves you… that changes everything, doesn't it? I would have to love you, too. Because that's what best friends do, right? If you make her happy… I would have no other choice but to support you two, always and forever. Because… because you love her, and you know her, and I know your love is pure, and I want you to know that I approve of you. I approve of you for Lily, for my Lily, my bestest friend in the entire world, my sister.
"But you have to promise, James. You have to promise me you'll show her you really care about her, that it's not a bloody crush, and that you'll always be with her, for her. You have to promise me that once you're together, you'll encourage her to be herself; you'll guide her to the good and best, you'll let her take her own decisions, but warn her about the outcome, you'll respect her more than anyone, respect her choices, her words, her feelings, her everything.
"It will not be easy, you know. She's different from all the other girls you've ever gone out with. She'll make you have a great time; she'll talk to you and make you laugh harder than ever before. But she'll make you have a hard time, too; she'll make you cry, she may break your heart from time to time. And she may give you the worst discussions of your life; she'll argue with you (sometimes she'll present the lamest arguments) and think she's always right. She'll be stubborn and never back down and she'll expect you to ask for forgiveness later. That's what girls do and that's what you'll have to endure if you choose to really be with her. With Lily, you can't have a simple teenage relationship in which you talk about kissing and clothes and how other couples do not look as good as you, you can't have that, not with Lily. If she commits, she'll fight for it and do everything in her power to make it last, to make it better.
"Now all you have to do is think James, think if Lily is worth it. If you love her enough to quit your immaturities and childish behavior, then I say go for it; but if you don't… quit it.