From last two three days, I was noticing this question, circulating over Quora. So I decided to shed some light there.
This confusion is only due to resemblance of names. Nefertiti and Nefertari were different individuals that lived approximately 50 years apart.

Nefertiti

The Chief Royal Wife of Akhenaten's full name was Nefer-neferuaten Nefertiti,  which means Beauty, or beautiful of Aten, The beautiful one, lived in the 18th Dynasty sometime between 1394 b.c. and  1340 b.c. Nefertiti is also known for a famous bust of her head, as show below.  
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Nefertari

The Chief Royal Wife of Ramses II's full name was Nefertari-Meri-Mut which means, The most beautiful of all the land, Beloved of Mut, and  lived sometime between 1292 b.c. and 1225 b.c.. Again these dates will vary. Nefertari had a temple built for her at Abu Simbel. All four great statues at the entrance of this temple are of Ramses II, while Next to the legs of the colossi, there are other statues no higher than the knees of the pharaoh. These depict queen Nefertari.