Putin has threatened so called unfriendly states to pay in rubles or have its gas supply shut off. It has said it doesn't buy things for free and so isn't going to charitable with its energy.
Europe has kicked against this with Germany saying its being blackmailed by this move. What other choice does Europe has with Russia alone selling about 40% of energy to the world.
To be honest, if European countries don't want to freeze to death then they inevitably have to obey the rules set by Putin. This step actually looks cruel but I see this is the last step from Putin to escape the sanctions imposed on Russia.
That's not true, the risks are not nearly as high as you present them, which is why the EU must impose a gas embargo on Russia. There's
the statement that EU already has enough gas till the end of winter. Now it's getting warmer, so the matter of gas will become relevant from the next heating season, starting in October. It's half a year away from now, and Germany buys around 40% of gas from Russia (so more than half is already covered by other sources). Also, the US said it'll help EU (and US has quite a lot of gas). Not to mention that if the Western world acted more swiftly right now, they could make the war end sooner, and then they could work out new deals with the new Russian government, including gas deals.