I lost my old peach tree, but when found it that was about 30 yo, I didn't cry. I had the foresight to buy and plant a young one a year before. In 2014 we got no fruit. We had a stretch of nearly -20 degrees F winter weather and it killed the buds on that tree, and on all of my apple trees, but, surprisingly NOT my young Bartlett pear. There were other problems, but I got about a dozen pears from that.
A local lost his entire small orchard from last winter and I figured out why I DIDN'T. My fruit trees have some protection bc they are southeast of farm building and due east and northeast of 30 ft. pine trees. The young peach and Bartlett pear are almost understory trees, and have a lot of protection.
PROTECTION, I think, is the key. If you plant your fruit trees due west, so that the winter can attack them, you'll lose them. I also looked for trees one zone north of mine, which we locals are rethinking is now Really zone 5. If you can buy local fruit trees from a nursery that carries trees bred for Canada, you might be able to keep them alive.