My Mother Suffers From Excessive Fatigue, Kindly Suggest

She is a hypertensive, 52yrs of age, she is on a combination of amlodipine and atenolol for 15 years. These days she gets fatigued in doing tasks which priorly she could do like making meals , some little cleaning job etc. She has never been in a gud health. She would not go to a doctor despite my persistent requests. Please give me some idea of what it cud be? she pracitses yoga , and she doesn't has any other major symptoms. she is perimenopausal her bld sugar and hematologist are normal, haven't gone for a cholesterol estimation