It is not my interpretation but simply the reading of the articles beheld in the treaty and the FACT that it was signed by all except Georgia signing in 1993
The signatories of the CIF on 21.12.1991 (including Ukraine) guaranteed towards the territorial integrity and the inviolability of existing borders and neutrality within the Commonwealth right down to a joint command of the military.
What does the CSTO of 2002 or it's earliest forerunner the CST 1994 have to do with the CIF signed in 1991?
Certainly not - the commitments/obligations are black on white - and Ukraine broke them in 2006. It simply did not come to any military action by Putin because of diplomatic talks and from 2010-2014 Ukraine was ruled by a president that had Putin's trust.
If it appeases you, one can also say that from 2010-2014 Ukraine was ruled by a men who was willing to sell out the Ukraine to Putin.
Okay, lets go back to topic, who destroyed how many of what today - after all this will be the deciding factor - right?