Concerned about my mom who won't take her medication, trusting only in Allah's healing

Assalamu alaikum, I need some advice. My mother has always been wary of medication. She's very thin, to a worrying degree. She smokes and barely eats, so she's often sick. She avoids doctors unless she's really ill, and even then, she might take prescribed meds once and stop. She has a chronic stomach issue and was given antibiotics, but she takes them irregularly. The disease persists and she complains daily. As her son, it hurts to see her suffer. I encourage her to take her meds, but she says she's never liked them since childhood and that 'Allah will heal me.' While I believe in Allah's healing, we must also utilize the means He has provided, like medicine. I get frustrated and sometimes angry. I try to respect her and speak gently, but it's hard watching her refuse help. She even mentioned that if doctors truly knew her condition, they'd hospitalize her, which suggests she's hiding her pain. This breaks my heart. I make dua, but I feel helpless. Has anyone dealt with similar parents? Jazakum Allahu khairan.