Many things left over my house when my dad left us were bills, tears and sadness.
The words tears and sadness in this sentence shows the extent of sorrow and pain in her life. This sentence also shows the burden of bills and life that was put on her mother shoulders after the father left.
I could not believe my house was like a hell
According to psychology when people are going through very difficult time, they don't believe it. This sentence exactly shows this situation. In order to protect her, her mind had helped her to not believe what hell she was living in after her father left. This sentence shows that heaviness of her difficult time.
But I know that inside the heart of each family member, there are small broken pieces
This beginning sentence gives reader at the very beginning the feeling that her happy family has gone through difficult times. Since the first sentence says that her family is a happy one, the second sentence says that their heart is broken from somewhere. This give the reader a sense that the family went through difficult days and overcome the difficult days.