My Dad is 65 and retired. He helps me every day....sometimes fence related, sometimes mowing, sometimes farm related. He has no desire to "retire" like normal folks. My FIL actually retired three times. He took an early retirement, and went to work for the competition for another 20 years. He was also in the Army Reserves for 25 years. He has now been at his part time retirement job for 17 years, and it's turned into six days a week and 10 hours a day. He told me not long ago that his income from pensions, SS, and the "part time" job is more than triple what he ever made while "working". The man that delivered a load of posts to us yesterday is 86 years old. He looks about 65 and was puffing on a Camel no filter....go figure. He told me that he retired once for a couple years but couldn't take the boredom. My Dad and FIL are both fit and look much younger than they are.
Do what you love, and you'll never work a day in your life.