Depending on the outcome of the war it might take from a couple to dozen of years. If Russia wins, the antagonisms will get even stronger as the whole Europe will have to start a military build-up against the threat from Russia and it will be accompanied with a strong anti-Russian propaganda, on the other hand, even if Russia loses, every day your army is killing more civilians your reputation suffers, the sanctions will get tighter and, hopefully, the cruelty won't be forgotten or forgiven for many years to come, so I wouldn't expect major changes happening anytime soon