Irishenglish is right in thinking that this is a complex issue.
Here is some historical background.
The Ossetians are mainly Christians, descendants of the ancient Alans, who once ranged as far as France. Their language is part of the Proto-Iranian group (IIRC). The Georgian language is completely unrelated. Plenty of loanwords in both, because of a long, shared history.
The Alans/Ossetians were frequent allies of the Iberians/Georgians in their struggles against the Roman and Parthian empires, and, later, the Byzantines and Sassanians. They frequently intermarried and the Ossetian nobility was heavily influenced by their Georgian counterparts. This is best seen in the Georgianised surnames.
The Ossetians were the finest craftsmen and blacksmiths in the Caucasus. Ossetian swords and daggers were eagerly sought after, even in Byzantium.   
The Alan kingdom became one of the strongest in that part of the world under King Durgulel the Great. He married off one of his daughters to a Byzantine generral, the other, to the Georgian king. He was strong enough to meddle in international politics, and dictate terms.
After his death, the Georgian rulers and feudal lords attempted to take over the southern part of the Alan kingdom. A situation not unlike the Anglo-Scottish Border developed, with back-and-forth raiding, as well as large-scale campaigns. Douglases and Northumberlands!
Eastern Georgia later fell under Persian rule, but Ossetia manged to keep it's independence, which it fought for tooth-and-nail.
In 1774, Georgia and Ossetia fell under Russian rule, but it wasn't until 1830 that Russia had any real control over them.
Let's skip over to 1917. Georgia became independent and annexed Southern Ossetia. They suppressed Ossetian language and culture, carrying on even under Stalin, who turned a blind eye.

Mind you. I don't think that Russia really is acting with Ossetia's best interests in mind, but rather to show Georgia what they can expect for joining NATO. One can only wonder what lies in store for the Ukraine.