From Healthcare.gov (the ACA, aka Obamacare, website):

"Medicaid expansion & what it means for you. Some states have expanded their Medicaid programs to cover all people with household incomes below a certain level. Others haven’t. Whether you qualify for Medicaid coverage depends partly on whether your state has expanded its program.

• In all states: You can qualify for Medicaid based on income, household size, disability, family status, and other factors. Eligibility rules differ between states.
• In states that have expanded Medicaid coverage: You can qualify based on your income alone. If your household income is below 133% of the federal poverty level, you qualify. (Because of the way this is calculated, it turns out to be 138% of the federal poverty level. A few states use a different income limit.)

…AND…

“If your income is low and your state hasn’t expanded Medicaid: If your state hasn’t expanded Medicaid, your income is below the federal poverty level, and you don’t qualify for Medicaid under your state’s current rules, you won’t qualify for either health insurance savings program: Medicaid coverage or savings on a private health plan bought through the Marketplace.”

source

States were given money when the ACA was implemented to expand the Medicaid. Many red states turned that money down choosing to let their poor residents continue to not get any healthcare coverage. Was that your friend’s state?