Attitude Problem

Recently, I wrote a nasty complaint about a colleague who has a terrible working attitude (knowingly that my boss might judge my language and my professionalism) but that's what I wanted to convey coz i could not tolerate this junior who has a serious work attitude yet 'good acting skills' in doing 'taichi'.
It was a task that is supposed to be done by her but instead she ignored. Some weeks back, I was an acting team leader that was responsible to delegate tasks to the team while my boss was OoO for the week and I was away later that week too. Well, basically everyone in the team are fully aware of their roles even before I delegate the tasks to them coz it is based on their support area/expertise. Before I left the office, I have even updated everyone (including our boss) that she is the assignee for the task. However, she acted as if it is not her job and even had the gut to tell my boss to chase me back when the job is due. There goes my complaint:

Dear boss,

Joey (not her real name) told me that she has not started on the assignment and has ‘returned’ back the task to me which I did not realised as she texted me only in messenger a week later (after I came back from holiday), instead of replying formally in email or by person.

It seems that she has been sitting on this task without initiating anything (while I was away), only to wait for time to pass and return it to me after I got back from holiday.

While she is still with the team, she has to be responsible in ensuring her current tasks are attended rather than keeping it silent.

I'm glad that I have reported her behaviour otherwise I would feel sorry to myself for taking over tasks from my ignorance teammate. Btw, this teammate has also been absent from work for 4++months straight since April (with all sorts of excuses such as: food poisoning, fractured arm/leg, skin allergy issues, vomit, diarrhea, difficulty breathing, asthma, husband fell sick, wounded/infection due to her pet cat bitten her and whatever funny/bizarre excuses that no one could even think of).

During her absence, i have been diligently taking over her roles/tasks as 'backup' and not even a word of thanks from her! Now that she's back, she gave me that sort of bossy attitude?!?

Seems like not easy to manage a gen-y staff...

Anyway, here's one cool performance from BlackPink to cool-down my anger...Well these K-Pop singers are gen-y too, but yet they strive in performing their best on stage...such a contrast from my 'teammate from hell'....sigh....