I Was Diagnosed With COPD Last Year. I Am 60

I was diagnosed with COPD last year. I am 60 years old. The spirometry was at 78% which is COPD level I. I was leaving air in my lungs. My lung X-Ray was clear. I quit smoking 4 years ago after smoking for 40 years. I never have had a cigarette cough...no coughing at all and I've never had Bronchitis. My MD prescribed Stiolto Respimat.
1. My question is how long do I have to live? I was on the COPD internet site that stated people diagnosed with COPD has about 12.8 years of life and quality of life greatly decreases.
2. Will finding out early and taking my medication reduce or slow down COPD?
3. COPD was detected when I was getting a physical. Since I had just turned 60, I went in to get my mammogram, colonoscopy, blood tests, bone density and GYN. The only side effect I have from COPD is I am out of breath climbing stairs. I currently retired with my husband to a 47 ft Hunter sailboat. We are sailing up and down the east coast and the Bahamas. Is there anything I need to know since I am not living a "normal" lifestyle? We are living out our dream. I walk a lot and must carry and climb daily. Can you give me any advice on how I can make the COPD slow down to a crawl since I want to be doing this in my 80's?

I thank you and appreciate the info you can give me on my personal way to attack COPD.
Joy M.