She did disappear, but if her kids were all doing fine, and the kids each had 9 siblings to turn of in case of trouble, I think she did her parental duty, and so why should she not follow her calling?

It sounds like she considered it for five years, most likely in communication with her children, and then decided to go ahead with the plan. Of the many things one could decide to do at age 60, this one doesn't sound too bad.