Well it's definitely not her family she's running from or else she'd be living with Shane in his home state right next to his parents. Instead he's the one who injected himself into her family life like a parasite, enslaving Hannah's mother and expecting Hannah's brothers and their wives to make him a priority too. Hilarious how that's his claim to adulthood and independence from his parents - finding another family to wipe his ass.
Hannah is absolutely fucked in the head. Whether her mental defects are nature or nurture, one thing is clear - she sought this life out exactly as it is. By design, her single identity in life is sexually pleasuring and caring for a disabled deformed baby man with the life expectancy of a horse, and she wants everyone to know it and follow in her footsteps. Might as well get NUTJOB tattooed on her forehead.