I have a fear about moving to the US not because I would "lose" my Canadian health care or that the company I went to work for wouldn't have a generous health plan but the fact that I have to care about it AT ALL.

The idea that at any point in time something could happen and I could lose my health plan and I am now at incredible risk scares me.

That's not actually true. A lot of provinces have waiting periods when you return to Canada after an extended absence. In the meantime you have to purchase private insurance.