No it's been said this is about him leaving New York for Denver. The Sweetheart is the city itself.

Canal and Bowery meet in Chinatown in New York. It's also known for it's out of town buss stops as it is at the end of the Manhattan Bridge and allows easy access out of the city. If you were going to leave New York, via Airport and didn't want to deal with the Jersey you would head there.

When he talks about what might have been this is his regrets about what he might have done in the city and that even as he is leaving she is (the city) standing next to him.

New York is famous for being a lonely place as it is so massive and that the "grind" of sleeping in the bed and getting up to face the city is taxing.