The US and Germany have been Ukraine's biggest supporters, but it must be understood that its immediate invitation into NATO is simply not possible while the conflict is ongoing. This would lead to a wider NATO-Russia war that could escalate further still.
If Ukraine becomes a properly confirmed member of NATO, it will show Russian Pres. Putin that he will be lost from a geopolitical point of view. As Ukrainian Pres. Zelenskyy said, Russia must recognize that Europe has borders and independent states, and everyone has the right to choose their own future.
Dragging Ukraine into the NATO military alliance is what started this whole conflict in the first place — particularly NATO's cultivation of Ukrainian nationalism that resulted in a violation of rights against the country's Russian-speaking citizens. Without eliminating the root cause of the conflict, it's impossible to achieve a fair settlement.