T-ara

Hwa Young, one of the members of the Kpop girl group T-ara, was recently booted from the groups.

T-ara is a K-pop girl group.

A few days ago, before Hwa Young left the her group, some members posted sarcastic tweets such as, "The important thing is how strong your will is the intensity of will." and this has stirred up all sorts of controversies.

To make matters worse, one fansite has turned into an anti-fan site called, "We require T-ara to reveal the truth of the matter."

I think T-ara will never be accepted by its disgruntled fans anymore.

it's -> it is
its -> belong to "it"

Hwa-young, one of the members of T-ara, was booted from the groups.

I usually see Korean names written as one, or with a '-'. In this case, I think it's important because 'young' is an English word, and could be confused.
Group - singular
I also agree with the way SarZ rearranged this sentence.

T-ara is a K-pop girl group.

This is correct, but would be better as SarZ arranged it.

A few days ago, before Hwa young left the group, some members posted sarcastic tweets "The important thing is the strength of your will." and this has stirred up controversy.

Controversy is an undefined quantity - it can still be plural.

To make matters worse, one fansite has turned into an anti-fan site, called "We require of T-ara the truth of the matter".

"Require of" is correct, but kind of awkward. Go with SarZ version :)

I think T-ara will never be accepted by it's disgruntled fans again.

'Never anymore' is odd. You want to say 'Never again.'