I live in cougar country right now in western Canada, but have never seen a cougar here, though I've often seen their prints in the snow.
Years ago when we lived on a farm on the edge of a paper company in Quebec, I did see a cougar passing through the meadow as I watched through an upstairs window. Eerie and extremely beautiful, he moved through the herd of cattle, longer than one of the calves and with his tail extended and his coat tawny.
My neighbors were skeptical when I related what I had seen, though the local college confirmed that, sure enough, cougars had once been native to the area and had a fifty mile or so radius of territory through which they would wander.
Later, when visiting the Museum of Natural History in Ottawa, I saw the stuffed version of what I had seen from my window. I was absolutely sure of it!
So though the official line is cougars don't live in the northeast of North America, there are the few oddballs out there such as myself who have seen them.