For that reason Russia probably do not want to deal with them and started building alternative routes.
Exactly... this is not Russia using gas supplies as a weapon, this is a country in the chain stealing gas and Russia getting the blame for that gas not arriving to the customer down the chain.
Now they are making demands as to how much gas they send down that pipe to keep their transit fees up... well that is up to the customer on the end because ultimately it is the customer on the end that pays the transit fees in the higher prices it pays for its gas.
If the customer wants cheaper south stream or north stream 1 or 2 gas then it is the customer cutting out the Ukraine as a transit country... not Russia.
There would be no value in spending billions of dollars building new alternative pipelines except for Kievs thieving and also the potential growth increases for Europe needing extra gas in case wind and solar do not perform as expected... which is already happening... sounds like Europe is exceptionally lucky they have two new pipelines coming on line that can boost supply if needed.