Hm, it's almost impossible to know how to properly contextualise the current story in Ukraine - the history is so complex. However, that's not my understanding of events - which I'm summarising below as neutrally as I can.
This position from Nato (linked above) set in motion a chain of events starting with the Georgia war a few months later. In order to join Nato, Georgia needed to regularise Abkhazia and South Ossetia as part of Georgia, and Saakashvili understood that this declaration indicated that if he were able to do so, then Georgia would be able to join Nato (some say this was told to him explicitly by US officials, but there's no hard evidence of this that I'm aware of).
In parallel, Russia understood the importance of maintaining the status quo in Abkhazia and South Ossetia to prevent Georgian accession to Nato.
Reports about the start of the war indicate South Ossetian separatists held a flame close to a powder keg, and Georgia exploded. Whether Russia was involved or not at this stage is unclear, but what happened next was a small Georgian armed force entered South Ossetia (and later Abkhazia) to impose Georgian control. Russia saw the potential implications of this, and fought back, ostensibly 'protecting Russian citizens', but in actuality, more likely to be trying to maintain the instability in these breakaway regions.
After just under 2 weeks of fighting, Russia rolled up to Tbilisi, and having achieved both their stated objective ('protecting Russian citizens') and the likely true reason for the invasion (stopping Georgia controlling South Ossetia and Abkhazia), agreed to a ceasefire, and eventually withdrew.
So, how does this impact on Ukraine, and what context does this add?
Ukraine leased a port in Sevastopol (Crimea) to the Russians, on which the contract was due to expire in 2017. As a result of the conflict in Georgia, Ukraine indicated that they would not want to renew this contract. Given Russia's size, it's quite surprising how little access they have to the seas, because most of their coastline is to the north, where only Murmansk is able to operate year round. As a result, Sevastopol is a critical strategic location for Russia, and so I suspect that this is when planning began in earnest for military intervention by Russia in Crimea. However, this also marked a turn away from Russia and towards the EU.
Now, a couple of years after the Georgia conflict, Ukraine elected a new president, Viktor Yanukovich. Yanukovich was not a new face in Ukrainian politics. He had previously won a presidential election in 2004, which was later annulled due to alleged fraud, and he lost in the re-run (the peaceful 'Orange Revolution').
Although there were fears about fraud in the 2010 election, it seems that these did not materialise, and Yanukovich was the legitimate winner of the election (although questions still remain about his funding and spending). Yulia Tymoshenko, his main rival, is quoted as saying that she and her party will never recognise Yanukovich as the legitimately elected president of Ukraine. In 2011, Tymoshenko was found guilty of embezzlement and sent to prison.
At this point, it's important to understand that more than 45% of the vote share went to Tymoshenko. Tymoshenko was seen as a left-leaning, euro-centric candidate, versus Yanukovich who wanted to dine at both tables. Almost half of the country felt as though the 'wrong side' had won the election, and their leader had been jailed (whether Tymoshenko was a political prisoner or not is a completely different essay).
In late 2012, the EU indicated that Ukraine needed to take several significant steps to improve various parts of their economy, judicial system, electoral system, and other items, which became an action plan in early 2013. Indications from the EU were that if Ukraine implemented these measures, they would be invited to sign an association agreement in late 2013, and Yanukovich was working actively to get these measures implemented.
However, additionally, the EU required Tymoshenko to be allowed to receive medical treatment outside of Ukraine. Further, a loan from the IMF which would help Ukraine meet the EU's financial criteria was predicated on Ukraine increasing gas bills by 40%.
This was not accepted by the Ukrainian parliament, and many in Ukraine felt as though the EU kept moving the goal posts deliberately, and were not negotiating in good faith. Ultimately, Yanukovich said that he wanted to explore other options, rather than joining the EU, and this is what triggered the Euromaidan protests.
Consequently, Yanukovich was ousted, and Ukraine continued to pursue EU association, eventually signing the agreement in March 2014. Yanukovich's period of active opposition to the EU was limited to winter 2013-2014 (although there are arguments he may not have been working in good faith before this, it's hard to tell definitively).
This was almost immediately followed by the annexation of Crimea by Russia, as they (probably correctly) felt as though the new administration in Ukraine were much more anti-Russia than previous administrations. It's hard to tell exactly why things have come to a head recently, but all of this is part of a story which is at least 20 years old, without even looking back through the 90s towards the collapse of the Soviet Union.
One thing that is fairly certain: Putin was likely not looking to be drawn into a protracted war, and was hoping for a similar outcome to Georgia: achieve political objectives (likely regime change) and then withdraw quickly. Given that this is no longer an option, and he has not achieved any of his objectives, I agree with the premise that the most likely next step is the 'Groznification' of Kyiv, unless Putin can meet his goals through diplomacy.