Why do Russians and Russian supporters, when talking about the Second World War, forget to mention that they received substantial American aid?

I'm sick of hearing this speech on social networks where people say that if the war was won it's thanks to Russia. That the Russians won alone.

Of course the Russians were essential to the victory, but many people tend to forget that the Americans provided considerable aid to Russia.
Why do Russians and Russian supporters, when talking about the Second World War, forget to mention that they received substantial American aid?
Why do Russians and Russian supporters, when talking about the Second World War, forget to mention that they received substantial American aid?
Post Opinion