Wow, do you have a picture of your plant? If it is 3 years old you have already kept it going a year beyond its life expectancy. It's a biennial and usually goes to seed in its second year. If you use a 'lot' of parsley I am surprised it has kept up with your needs. It must be enormous. I grow 6 - 10 plants for our requirements.

Not huge anymore, since I used a ton of parsley for yesterday's dinner in cooking, plus a lot for garnish, so the poor plant looks kind of butchered, but I'll see what I can do with my old digi camera.