You get used to being 'less than nothing' if you're told that lie enough times, if you believe your only purpose in life is to take the blame and that a whippin' is all you're good for.
Daryl had known these things for much of his life. During his formative years, he was 'the Dixon kid', Merle's little brother, constantly trying to drop the family legacy while dodging other people's crap. As time rolled on, he graduated from 'the Dixon kid' to 'that Dixon punk', and the helpless anger of the sensitive child became the badass attitude of the young adult.
He got by pretty much alone most of the time, and he figured that was just the way things were.
Then, one weird day, when the world turned to shit and the streets were stained with the blood of the sleeping and the air was heavy with the stench of the walking, Daryl finally began to find his true place: tracker, bowman, defender, friend.
He found a family in some good people who depended on him…
…and he found love with a sheriff whose kiss gave him hope for the fate of humanity and whose arms felt like home.