Your Mom will be fine without her "blood pressure pills".
If they're beta-blockers in fact, not taking them will actually lower her risk of stroke
or heart attack
, if her cardiac function is actually impaired.
Your pestering her does not help, and will be increasing her stress
it's her life, her health, her decision, -let her live it the way she wants to. - In the same way you'd want to live yours, without her nagging you.
Honest, - the pills won't even be noticed...