J.k. Rowling said this quote

After all this time?Always...

~ J.k. Rowling

Your mother died to save you. If there is one thing Voldemort cannot understand, it is love. Love as powerful as your mother's for you leaves it's own mark. To have been loved so deeply, even though the person who loved us is gone, will give us some protection forever.

~ J.k. Rowling

Snape's patronus was a doe,' said Harry, 'the same as my mother's because he loved her for nearly all of his life, from when they were children.

~ J.k. Rowling

Ginny, listen...I can't be involved with you anymore. We've got to stop seeing each other. We can't be together.It's for some stupid noble reason isn't it?It's been like...like something out of someone else's life these last few weeks with you. But I can't...we can't...I've got to do things alone now. Voldemort uses people his enemies are close to. He's already used you as bait once, and that was just because you were my best friend's sister. Think how much danger you'll be in if we keep this up. He'll know, he'll find out. He'll try and get me through you.What if I don't care?I care. How do you think I'd feel if this was your funeral...and it was my fault...

~ J.k. Rowling