Growing up being shy is hard but being in an adult in a world that requires extroverts is worse.
As an introverted child people were scary. You cried at strangers and maybe even some family members. Now as an adult being introverted just makes everything worse. There is no parent to hide behind or speak for you so you are forced to come out of your comfort zone.
Being introverted comes with the strange feeling of having no interest in being involved and realizing that you want to involved you`re too scared. Having to walk up to people is some that you might dread. Smaller groups of friends make you much happier.