When she left

Today was Tuesday. When Xi came into the office, she said "Hello" to me. She had had seven days off, but still looked a litter tired. Then she had a talk with our boss, and fifteen minutes later, they came out the meeting room. Xi began to clear up (pack up) her stuff.
"Do you want to leave now?" (Are you leaving now?) I closed asked/whispered to her.
"Yes. I'm I have not been feeling well recently. "
"When will you come back?"
"Maybe next month." She tapped (patted) me on the shoulder and said, "Don't worry about me". 
Well, in fact, I didn't wasn't worry worried about her at all. She had was always been always absent for no reason and had been doing done her job with a negative attitude for a long time. No company wants such employee. I have had known her ending in our office she would have to leave soon.
But, I was not feeling happy when it really realized happened.
I accompanied her to the door. I didn‘t want to ask what had happened to her, and why did she perform she had been performing so terribly. Because we were not friends, so I can't couldn't. We walked in silence.
"What I can tell you only is that I'm not me at present", she suddenly opened her mouth and said.
"What?"
"I'm not me recently. I can't explain what happened to me. It's to sad and to woeful. I won't tell you anything, but I will call you my sister." she smiled chokingly.
"Well," I attempted to comfort her, "Everything will be going well fine, don't worry. And don't cry."
But she cried, "I have already cried for many times."
I can't couldn't do nothing but embraced her tenderly.
Finally, she calmed down and said, "Goodbye, my sister. I will take care of myself, don't worry about me."
That's the first time she had called me sister since we have had known each other. I'm a year older than her.
"Our company will hold a birthday party for you and me next month. I hope I can see you at that time."
"Your birthday is in June?"
"Yes."
She smiled, "OK, I will give you a present." Then we said goodbye to each other, and she left.
I stood still in the door until her figure disappeared on the street.

Good job! I think you are an very good writer. Keep it up :-)