Mine

Mine by Taylor Swift is featured in The Break-Up, the fourth episode of Season 4. It is sung by Santana.

After the apparent "rapture" staged by Kitty at Breadstick, Brittany   points out that what everyone saw at ‎Breadstix represented how Brittany felt when Santana left her. Santana looks upset as she sits in the choir room, welcoming Brittany in. They sit and Santana says that things grew apart after graduation and that the choir room was the only place where Santana could stand out and express her feelings through song, and so, Mine, begins. Santana sings to Brittany teary-eyed, leaving Brittany crying at the end of the performance.

They hug, but they talk about their long distance relationship and cheating, and how they won't do it to each other, other than the fact that Santana had a small "attraction" and Brittany may have too. Santana then says it won't be an official break-up, but it will be a short break for the both of them. Brittany, in tears, says that it feels like a real break-up.

Lyrics
Santana: You were in college working part-time waitin’ tables Left a small town, never looked back I was a flight risk with a fear of fallin’ Wondering why we bother with love if it never lasts

I say "Can you believe it? As we’re lying on the couch?" The moment I can see it Yes, yes, I can see it now

Do you remember, we were sitting there by the water? You put your arm around me for the first time You made a rebel of a careless man’s careful daughter You are the best thing that’s ever been mine

Flash forward and we’re taking on the world together, And there’s a drawer of my things at your place You learn my secrets and you figure out why I’m guarded, You say we’ll never make my parents’ mistakes

But we got bills to pay, We got nothing figured out, When it was hard to take, Yes, yes, this is what I thought about

Do you remember, we were sitting there, by the water? You put your arm around me for the first time You made a rebel of a careless man’s careful daughter You are the best thing that’s ever been mine

Do you remember all the city lights on the water? You saw me start to believe for the first time You made a rebel of a careless man’s careful daughter You are the best thing that’s ever been mine

Oh, oh, oh

And I remember that fight Two-thirty AM When everything was slipping right out of our hands I ran out crying and you followed me out into the street Braced myself for the "Goodbye" ‘cause that’s all I’ve ever known Then you took me by surprise You said, "I’ll never leave you alone"

You said, "I remember how we felt sitting by the water And every time I look at you, it’s like the first time I fell in love with a careless man’s careful daughter She is the best thing that’s ever been mine"

You made a rebel of a careless man’s careful daughter You are the best thing that’s ever been mine Do you believe it? We're gonna make it now And I can see it I can see it now

Trivia

 * Originally, Naya was supposed to sing Bad Religion by Frank Ocean, however it was switched with this song. Source
 * Heather was really crying during the scene, no fake tears. Source