"Hey, who is he? What were you two talking about?"
"None. I was looking at the sea and he came to my side to say 'Hello.'"
"And you started to tell him your life story?"
Ella rolled her eyes. "Don't talk nonsense."
I need an idiom for the underlined part. She talked to a stranger very long time, so her sister wondered what they talked in so much time as if she told him her whole live story. It's an idiom in my language and don't know if it is used in English, too. So I explained it but if it is understandable, ignore it.
"So you had to tell him your whole life story?" is a very natural thing in this context.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.