Why she is the only who died?

This morning i felt the loneliness

I lost my friend - Cai Fun

Because of a traffic accident last night

She was a girl full of goodness and filial piety

I treated her as my own sister

But now

She had passed away

Why?

Because of her boyfriend

He is a bad guy

He likes to drink

He likes to race car

He is irresponsible

He destroyed my dear

If

She did not love him

She would not be together with him

And

She would still alive

Why?

Why my dear was the only one who died in the accident

But not her boyfriend

explcit conclusion

If Cai Fun was not his girlfriend, she would not be with him and she would not die