Time to stop funding Ukraine?

By the same token, you could equally say that the UK and other NATO countries are doing the same thing.

Winning the war is not just a matter of the sort of resources the US has given Ukraine. To end the war soon would likely need contributions in the form of nukes or at the very least boots on the ground, and no country is willing to do that because that would spark a wider conflict. I think that the US has already been exceedingly generous to Ukraine and I'm not even sure that they could have given Ukraine more resources than they already have without depleting the supplies they need for their own protection. But why do you think it's America's responsibility to solve this problem? America isn't at risk. Europe is.

If Europe becomes a formidable military force, they will not have to rely on American generosity, which in my opinion is a good thing, because American generosity always depends on who is in power and what the Opposition wants, and as we are seeing of late, aid to Ukraine can be delayed for long periods because of political squabbling.
Resources or not, I don't see Europe becoming friends with Russia any time soon, do you? Russia is failing a lot faster than the US.

You will find out just how generous the US has been if they withdraw from NATO altogether. It seems to me the US is damned if they do and damned if they don't. They're blamed for acting like the world's policeman and blamed when they don't. If they don't give enough, they're blamed for allowing bad things to happen. If they do give enough, they're blamed for benefitting from the situation.
Surely you are not saying that Europe could have become a military power power to rival the US if only the US had encouraged it? 
The world would be a better place without international conflict. Isn't that everyone's ultimate goal? 

They are not only political allies but also trade partners. In a perfect world we would all get along, but sometimes aggression requires a response and the US has been able and willing to assist. 

What nation gives the interests of another nation priority over its own?

Then why should it surprise you that the US acts in the interests of the US?

It reassures you? Why is that? And who thinks America doesn't act in its own interests? 
I am not saying that America isn't philanthropic or that it acts in its own interests to the exclusion of all else. When nations have interests in common, they all benefit from alliances.

Reagan liked to wax sentimental, but I don't think that the 'special relationship' is at all diminished because it exists out of mutual interest. Both sides benefit from extending special consideration to one another that they don't necessarily extend to everyone else. 
The Americans I know don't see themselves as amoral predators. They see themselves as well-meaning, generous and philanthropic.