How does one break free of their mental problems?

I have an abandonment complex…
And a “my mommy didn’t love me” complex.
I’ve been thinking lately, both of those play a pretty big part in who I am today. It takes a lot for me to let people in or trust someone even a little. I don’t stand up for myself and I don’t have a lot of self value. I feel like most of these are pretty common stories. How do other people break free of these issues? Coping suggestions? Anything?