She knew it could never last forever, even if she kept saying that she would never leave him- somehow she knew that one day all this wonder would stop and she'd be back in her dreary old life. So she took everyday as a blessing, kept soaking up every sight and stored away all of his smiles and cataloged every tune of his laugh; so that when she was back, the memories would keep her company, keep her afloat after he left her. How could she ever know that along with her heart, he'd take her memories too.

**

Okay, I know you don't know Donna yet, but it seems she's the only Doctor Who character I can write.