There are rescue animals who were abused by their prior owners and which, with the right new owner, recover nicely. Granted, some do not and will trust only their new owner and not anyone else. Still, that is some progress.

I guess it is similar with humans. If you were abused as a child then you may always be nervous and untrusting with strangers. But, hopefully, you have made some friends and have learned to trust them to the extent that is possible. It's a slower process and a disadvantage for sure. It requires giving people who you don't know well the benefit of the doubt until you learn if they are trustworthy.