How do i know

So there's this girl I know
She's 17 years old 
She was born on November 1st 
When she was almost 3 
Her dad passed away 
Her mum was cheating 
So he topped himself 
Then her mum got a new boyfriend 
The guy she was cheating with 
He moved in with them 
When she was 3 
He started touching her 
By the time she was 5 
He was having his own way with her 
Her mum would abuse her 
Se would put smokes out on her skin 
Kick her
Punch her
Leave her in filthy clothes
Not feed her 
She hardly went to school 
The days she did 
She would get bullied 
For looking the ways she did 
She had no one 
Becuase he sister left her 
But
Her sister came back 
When she 13 
To take her 
To live with her 
To love her 
And that's exactly what her sister did 
But it didn't get better 
She stared drugs straight away 
Herion 
Cocaine 
Ice 
Weed 
She got multiple personality disorder
She would talk to guys 
But as soon as they found out about her 
They left her 
Becuase they didn't want to be with someone like her 
Well that's what she thought 
She met this one guy 
He was perfect to her 
That's what she thought 
But they both did drugs 
Which wasn't good 
And she realises that now 
She was with this guy 
For 2 years 
And she fell pregnant 
With a baby girl 
But her baby girl 
Passed away
With her dad 
She the quit drugs 
A few months later 
She started dating another guy
That got her on drugs again 
And got her pregnant 
This time it was a boy 
But the boy had heart and lung problems 
She got told he wouldn't live till one 
And it was true 
Becuase he passed away a few months later 
She met this one boy 
That got her off drugs 
It has been 70 days 
That she hasn't done drugs for 
She still tries every day 
Not to think of her past 
Not to do drugs 
Not to fall so hard 
how do I know because that girl was me