Environment plays a very large part when it comes to our mental health.
We are a product of our environment and this is why often times those who do not learn emotional regulation, hurt others.
At some point in life we become aware of this pattern and that awareness presents us with a choice.
We can justify our choices with excuses and repeat familiar patterns or we can dig deep, figure out exactly why we are the way we are and refuse to inherit dysfunction.
Ultimately we need to choose to break the cycle ourself in order to learn new ways.
Not everyone is willing to do this.