The EU should have thought about that when they aided and abetted the destabilisation of the previous and democratically elected Ukrainian government.
This, there was a signed agreement between all parties that Yanukovich would step down.
Euromaidan did not like that, so they staged a coup which went against all agreements reached on international level.
They forcefully overtook whole government and we supported it.
The mess Ukraine is in, is its own and only theirs fault... If Yanukovich left as agreed and Poroshenko came to power,Ukraine would still have Crimea and Donbass while still being pro-EU.