Why would a slim healthy active 80ish woman need a pacemaker? Complain too much?

Interesting question. Being slim, healthy and active doesn't preclude someone from needing a pacemaker. A pacemaker is used when there is some sort of electrical problem within the heart that prevents it from beating properly. This can happen to young healthy people as well as older people, skinny people as well as fat people, athletic people as well as sedentary people.
Slow heart beats. Pacemakers are recommended to patients when there is evidence they have too slow of a pulse, or evidence that the electrical system between the top and bottom chambers of the heart is weakening. This may happen even in slim, health individuals.