"it's got to be really warm for me to start on the cold!"
That used to be the case with me also, however I am reducing the hot water little by little. I have found a few "mental" things that help a great deal:
1. the feeling of hot and cold to me now is the same on the skin...
2. I close my eyes and picture myself under a free flowing clean waterfall
In addition, the alkalizing, diet and exercise efforts have definitely improved my tolerance for hot and cold. Last summer I tolerated the heat better than I have in more than 7 - 8 years. I have yet to wear even a jacket this winter and spring is approaching.
That said, you live in a colder climate than I do and I am sure your cold water is markedly colder; you got me beat by a long shot.