Assuming that is true, if your neighbor stole your car would you still pay for the gas to keep it running? Answer truthfully, I suspect you wouldn't.
If Russia had not seized Crimea then there would not have been a water issue.
Sevastopal is in Crimea and Ukraine’s flirtations with Nato caused the annexation. Russias largest Naval base was not going to be infringed on. Over 90% of Eastern Ukraine Russian Speaking residents were in favor of becoming part of Russia. My ex is from Kherson, I have friends writing me from Odessa every day and I have spent a total of 2 months there on 7 different occasions. I pay attention...
The population of Crimea is overwhelmingly Russian, owing to its historically strategic Russian naval and military bases, so the 2014 vote to secede from Ukraine after the Kiev coup was no surprise. The vote was 96% with an 83% voter turnout.