If Rosalie didnt have Emmett how would her life be?

awful, they're ment to be together.

She would probably be extremely and utterly depressed and would have to end up with Edward.

Worst then now.
No one would want her.

my opinion.

Ok in the book it clearly states that Rosalie would give up anything for a baby even Emmet.

She wpuld feel sad but she is a beauty and men will be attracted to her easily

Hoped this helps

probobly she'll be depressed