If you weren't privileged to inherit a secure attachment style in your childhood, then you are in my club of people who earn/learn their secure attachment style.
Here's the three phases of healing you'll need to work thru...
1. Reflect: on your early attachment relationships and how they impacted you
2. Grieve: feel the feelings of loss and pain related to not having secure relationships to lean on and find confidence in.
3. Grow: change your patterns of relating and work to learn new ways of showing up in your close relationships.