The House of Representatives attempted to repeal Obamacare. It was initially stalled because moderate Republicans and staunch conservatives could not reach an agreement over how it should be replaced.
Democrats did not think it should be replaced at all.
Eventually, Republicans did agree on something and the issue was taken up by the Senate where the same thing happened. Republicans could not agree on anything and Democrats refused to help.
The Trump administration officials in charge of getting Republicans in Congress to pass a tax reform package are now finding it difficult to bridge the divide between moderate and conservative Republicans.
If something cannot be worked out between those two groups, then Democrats will be needed to pass anything. For now, few Democrats are inclined to help.
