Family problems

For a year my brother and his wife relied on us for everything from nappies to clothes for their two kids as they said my brother was not earning enough in his commission based job to cover their mortgage. They borrowed $12000 from my parents to avoid losing their home. A year later I learned my brother hid a drug and gambling issue from me - everyone else in the family knew. I confronted them for being dishonest and they were also not paying back my parents but buying the latest of everything (unbeknownst to my parents) and I stopped helping as much. Since then they constantly cancel plans with us, even Christmas Day celebrations two years in a row and limit my contact with my two nieces. They have time for everyone else. I’ve tried telling them how I feel, I’ve stopped constantly giving and they just get more distant. My daughter is an only child and I would love for her to have family connections but not one that relies on us giving all the time. What should I do?