So the two main parties in America, the republicans and democrats. Is it true there was a time when both parties weren't so different?

The parties have always had differences, but there used to be overlap in the middle. Now there is literally none, where the most liberal Republican is still more conservative than the most conservative Democrat. There is essentially no compromise, and no desire to work together to accomplish common goals. The Republicans no longer have a party platform that articulates what the party believes in. They don't see a need to have one.