Question

Why did Gautam Buddha leave his wife only after one night?

Answer 1

In short - Siddhartha was disgusted by the corruption, thirst of power, selfish ambitions and jealousy among people in politics. He was aware that true liberation from suffering won't come from mere social works and changing social rules but from inner transformation of individuals. And he wanted to find a way which can give true liberation to people. He had heard the names of some famous teachers many times who were well known for their achievements in meditation. He couldn't wait to become old to pursue the path of inner transformation and to find the way out of suffering (which were normal tradition in India those days). Yashodhara (his wife) also knew that someday Siddhartha will leave her to find the way for which both of them were working. She even might have planned for his escape from the palace.Long story -

Siddhartha and Yasodhara’s wedding took place. King Suddhodana was at peace, now that Siddhartha had followed the path he had wished his son to follow.

Answer 2

Because he wants to come to know about the outside world