I'm currently in the U.S. and leaving shortly, will soon have been here just under the maximum time allowed, I'm fine leaving and could happily visit Canada at another time, yet was wondering if I was able to fly to Canada from the U.S. and stay in Toronto with my friend, before flying from Toronto back to Manchester when I'm ready, I have no intention of returning to the U.S. for a long time except for potentially visiting family in July, I just wouldn't want my short trip in Canada to add to my time in the U.S. when I'm not heading back there, and thus disrupting any plan to return in the future.
There is no problem with you doing this.
Although it's well known that 'a visit to Canada doesn't reset the VWP clock', that only applies if you return to the US from Canada. (Technically if you don't leave the zone including Mexico, Canada and the Caribbean islands before returning to the US). If you leave the US to Canada and then return home from there, you are counted as having left the US on the day you left the US.
This assumes that your flight home is direct from Canada. If your flight home involves transiting through the US, there is potential for you to be denied entry when the flight reaches the US, though in practice it's unlikely if you are clearly in transit and have the necessary tickets.