Pity for her...

I am a librarian and I am currently preparing for my final exam.
She's (who is 'she'?) also a librarian and librarians of same age with as us are ordered to prepare for this year dinner. I mean (the?) librarian's dinner. (This last sentence is a little confusing. Is the librarian's dinner a big event?)
Unfortunately, the place is an open space out in the open and it rained quite heavily last night.
She (who?) is the one who prepared so much and sacrificed her time and energy, but it all wasted in a the blink of an eye.
But Thankfully, the former librarians helped us to make the situation better. ('helped us resolve the situation' would sound more natural)
It's indeed a pity for her.

Good work!
In English it sounds odd not to specify who someone is before you refer to her as 'she'. Other than that you only made a few minor mistakes, and I changed some things to make it sound more natural.