Sain wedi'i Rhannu

AITAH for telling my father to accept that my brother isn't my responsibility? I (35F) have a complicated relationship with both my father and his wife “Denise” (fake name) for several reasons, some of which relate to my half-brother, “Jake” (9yo).  There’s a lot of backstory here, but to sum things up: Jake exists because Denise wanted a baby and my father was upset that both his daughters were moving out. They expected me and my sister (29yo) to have an active role in caring for Jake. That wo