Sure it's a divided country. No question. You don't bomb countries for being divided. Had Putin stayed in the Dunbas area that would have been a moderate excuse. He chose to attack the entire country and assassinate the elected president.
You sound like the people who tell a beaten wife that she shouldn't have talked back... Putin is a criminal and you're making excuses for him. He tried to take Ukraine in the gentle way by installing a puppet. When that didn't work he's trying force. Ukraine was distancing itself from Russia because of Putins policies.
You're picking small things to justify terrible HUGE things. If someone says something bad to you on the street shooting their head off would be justifiable?
That's the level of excuses I'm reading here.