Change jobs: Should I or shouldn't I??

I'm a 56 year old healthy, active women who works in healthcare. I do homecare as an Aide for a large non-profit organization where I reside. I worked for this company for 3 years now and while I LOVED my job. I'm starting to not like it so much now.
I used to get raving reviews from all my patients who loved my work ethic and my company recognizes it sometimes. But it's all my manager does now never gives me accolades on my achievements but nothing but badger me However, lately I've had a few (3) complaints in the last year. It was brought to my attention in a meeting with my manager and her manager, and quite frankly, was caught off guard. Apparently, this "incidences occurred" over 6 months ago and when I brought up why are you mentioning this to me now? My manager stated that she was too busy. (yeah,ok) Anyhow, I'm thinking that maybe I should leave and look for another opportunity.
My concern is, I'm getting older, 56, thought I'd retire from here but I don't think I can hang in anymore. I'm not as happy as I was working here. I'm stressed and tired of the abuse by this manager.