I feel betrayed that a democrat administration pushed to repeal that ban.

I guess you can feel a little less betrayed.

Today, the Supreme Court (SCOTUS) ruled 6-3 under its conservative supermajority that a bump stock attachment does not convert a semiautomatic rifle into a machine gun, which is prohibited under federal law. Under this decision, civilians now have access to bump stocks again.

https://www.pbs.org/newshour/politics/supreme-court-strikes-down-bump-stock-ban