I'm afraid you're confusing separate issues.
One, W. European countries want friendly neighbours. They're prepared to pay to get that, in the form of aid.
They're not alone. Russia has paid Belarus quite dearly to remain friendly, and this is not the only example. The West is hardly unique in this.
There's also (& this is something that I find Russians are generally baffled by) an element of ideologically-backed altruism. They sincerely believe that democracy, human rights & so on are good things, & they wish to promote them. That doesn't preclude deep cynicism on their part in other respects, & it's also affected by their belief that democratic countries which respect human rights will be good neighbours, but even the most power-hungry & self-serving mainstream politicians in western Europe generally really do think that democracy & everything that goes with it is good, & worth promoting. It sometimes leads them to make mistakes when dealing with countries where social & political conditions are very different from those they're used to.
It's not altruism. It goes back to the first point you make. There's an ideological component here, yes I agree. But here we get into the fact that states are not black box rational actors. There are a whole slew of under currents, and in liberal-democratic regimes the under currents can dominate the political agenda. While the President may genuinely believe that he is out to help Ukrainian democracy, he is elected with corporate money, and that corporate money cares little for democracy or politics at all. They want their economic interests protected at any cost. Hence what politically is being presented as a deal to promote Ukrainian integration into Europe is really a treaty created by robber-barons to take over a new market. The political elites altruistically battle evil Russia in the name of freedom, while the economic elites quietly ensure that their interests come first. Such is the nature of capitalism. Economics are the basis for the political superstructure, not vice-versa.
And you're wrong, completely wrong, about the EU being expansionist.
I'm sorry but no matter how you want to talk about it, the EU
has expanded rapidly, and has fought against Russia politically and economically (sanctions, trade barriers, democracy promotion) to take countries and markets. If Russia funded a political party in the west, that played a central role in the national politics of a large country, overthrowing an elected government and inserting itself into its place, Russia would be accused of supporting an illegal coup d'etat. When the EU does the same in Ukraine, it's "non-expansionism and altruism". Really?
There are arguments about whether it was right to accept some of the existing members, arguments about whether to allow in some of the current candidates even if they manage to meet the conditions, & flat refusal by many (most?) to believe in the possibility of some countries ever being candidates - e.g. Ukraine. The current members have to agree to admit new members. There's no driving force to expand.
The driving force exists at the Union level. While many individual member states have a problem with rapid expansion, the EU as an entity doesn't. And it's continued and successful attempts to suppress individual states sovereignty in the name of presenting a united front or adopting a united policy are evidence of that. It's easier to pressure a large number of smaller (relative to the total size) countries. What chances does Hungary have of unilaterally opposing an EU-wide policy on sanctions? Basically none. But imagine if the EU consisted of only Britain, France, Germany, Italy, and the Benelux. And Italy and France were opposed to the sanctions while Germany and Britain were for them. Now it only takes two countries, and the EU has to behave like an international organization, a forum of countries, rather them a country itself.
BTW, the admission of most of E. Europe was seen as welcoming back long-lost brothers by many, a return to a previous era of open borders (to travel & trade) between Russia & the Atlantic. That's finished. Everywhere it covered is now in the EU, or has chosen to stay out - & is left to stay out, as it wishes.
Re-annexing Ukraine is welcoming back long-lost brothers and a return to an era of Slavic unity and friendship.
As for countries wishing, if you're in the business of interfering directly in internal political processes, the idea that they are "left as they wish" is patently absurd. Hence why democracy promotion and economic bribery/bullying are simply different means of coercion. Soft power is power none the less, and can be wielded to devastating effect. The fact that the EU prefers to use it as means of expansion simply shows that they are better at it then Russia.