My brother's $50 dinner guilt trip exposed our whole money dynamic

Last Tuesday my brother took me out for my birthday and picked a fancy steakhouse downtown. At the end he made a big show of paying, then joked I owe him one since he knows I'm the 'responsible one' with savings. That comment hit different because I realized I've been quietly subsidizing his lifestyle for years, like covering his half of our mom's prescription costs and loaning him $300 for car repairs in June. He never asks, he just expects, and I never push back because I don't want an argument. So I finally told him I'm not comfortable with him treating me to meals if it comes with a hidden bill. Has anyone else had a sibling turn a gift into a debt they can call in later? How did you shut that down without blowing up the family?