Why didn't Jenny marry Forrest Gump from the beginning?

Because she knew that her life journey had not yet begun, she felt that Forrest Gump was not good enough for her. If she had married Forrest Gump from the beginning, she might have been in that small town with Forrest Gump.

Having lived all her life, she is full of curiosity about the outside world and energy for her dreams, so naturally she will not stay in this small town.

Later, after all kinds of life, I finally chose a stable life and felt that I was not worthy of Forrest Gump. Yes, I changed my mind later, which is also true.

Why did she choose to leave Forrest Gump before she got married and choose to let her children know Forrest Gump after making changes?