Teardrops on My Guitar -- Taylor Swift

I bet she's beautiful

That girl he talks about

And she's got everything

That I have to live without

Stella never thought that she would see the day that she hear Mac Taylor talk about another woman like he used to about his late wife, Claire.

It both made her happy and it saddened her. She was happy that he had finally moved on again after the hurt that Payton had put him through. But she was sad because she had always held a hope that he would see that she was there, guarding her heart from everybody, except him. He was the only one that she could ever again give her heart to. She would keep it more closely guarded because she was not going to let it break just because her best friend had found somebody that made him happy.

The rest of the lab could only wait and hope that she would realize that, even though he never said a name, he was talking about her.