Disclaimer: None of this is mine. It is all J.K's. I only embellished on her story a little.
Note: the things that are italicized are the characters thoughts.
Mrs. Nymphadora Tonks Lupin
Concentrate Tonks, Concentrate, she thought to herself.
There, right in front of her, was her aunt Bella. She couldn't help but think of all of the death and misery that one person caused.
Well Tonks, you could make all of that rebound on her if you just concentrated! She thought violently to herself as a jet of green light whizzed past her right ear.
For a split second Tonks thought that she saw Remus out of the corner of her eye. She turned her head slightly only to see a jet of green light hit him squarely in the chest.
Tonks screamed and ran towards his dead body. How could you let this happen? She thought to herself. How could you let this happen to him!?
She gave a roar of contemptuous anger and ran towards his killer, Dolohov. She fought him with such ferocity that he stumbled with surprise and screwed up his face.
Bellatrix sighed with boredom. This is going to be way too easy. She thought playfully to herself.
She raised her wand and thought for a moment. How nice, I get to kill both my niece and my nephew! Pity, she could have been such an asset to the Dark Lord. Pretty face too. Glad to be rid of her though, to much trouble to be kept alive. After all, she insulted the name of the Dark Lord!
And with that, she casually flicked her wand and screamed with delight, AVADA KEDAVERA!
The spell raced towards Tonks but she took no notice. The only thing on her mind was that to avenge the death of her husband.
In a fraction of a second the spell collided with her back.
A felling of sorrow crossed her mind, but she quickly wiped it away when she realized that wasn't what Remus would have wanted.
And with that, she died. Her limp body fell next to Remus's and they lay there, husband and wife. Now and forever more, would they be together.