(I am not a teacher)
five-year-old girl that had to face up alone to such a situation!
I would say "five-year-old girl who had to face such a situation alone!"
who was the same age as me
I would say "who was the same age as I"
my family and myself took the decision of turning over a new leaf:
I would say "my family and I made the decision to turn over a new leaf:"
It was in those fantastic atmospheres where I grew up…
I would say "It was that fantastic atmosphere in which I grew up..."or even better "That was the fantastic atmosphere in which I grew up..."
The other parts of your text in bold appear just fine to me.
Student or Learner