There are many reasons why your parents may not have given you what you needed.
But now that you're an adult, it's up to you to become the parent to your inner child that you needed years ago. Whatever your relationship with your parents now, you have to be responsible for your wellbeing. And that takes a willingness to clearly see yourself, them and how you interact.
Responsibility for your wellbeing means that you're honest and accountable to yourself - and they are accountable to themselves as well. Disentangling from past influences can be difficult and time-consuming, but that's how you free yourself from damaging beliefs.
So begin by answering these questions: what do you want to give your inner child? As parent to a fearful and vulnerable child, do you know how to give them what they need?