The might of the Russian army haven't managed all that much in three years against Ukraine, regardless of where weapons have come from, but our supposed alliance of nations is scared to put Putin in his place...
It's definitely about money for Russia (and for Trump) and Putin's definitely got something on Trump. Sticking it to the West is no doubt a big motivation as well, both for maintaining his hold on power and also because it's just how he thinks, given his background
Unfortunately the current situation was encouraged by allowing Russia's prior annexations - those were a little test of the water and the EU and US proved themselves to be weak enough to make his invasion possible. He's not had the warm embrace that I believe he was expecting though.
And now Trump's withholding weapons and intelligence - he couldn't be helping Putin more. With allies like that...