Why is NATO at Russia's doorstep? Never saw so much outrage from westerners over US invading countries thousands of miles from home over bogus security claims or to "restore democracy", killing millions of civilians.
Two wrongs don't make a right but from Russia's perspective having NATO set up shop near their borders is a matter of national security.
I would also encourage you to talk to people from both Russia and Ukraine around the Donbass to get an understanding of what's been happening the last 10 years.