If you're in oil you're always at risk of being cut in the inevitable down cycle, especially places like Canada with relatively little light sweet crude. Countries like Russia and Iran stop causing trouble whenever oil bottoms out. Even the once unassailable likes of ExxonMobil, Halliburton, and Saudi Aramco have been cutting during the last several cycles, nevermind fallen giants like BP, Shell, Pemex, and PDVSA.
Maybe you can get an MBA, accounting, nursing, or law degree in the next downturn. Those are pretty popular options.
As for refineries, Canadian heavy sour crude sucks. It's expensive to refine, best used for building roads with asphalt (hence Chinese demand), and no one in the Western Hemisphere but the US Gulf wants to refine it, not even Mexico and Venezuela in their heydays, and Venezuela is all heavy stuff.
If you wanted to build a refinery from scratch, you'd have to spend probably $10 on just the plant, THEN you'd have to have the infrastructure to pipe crude and natural gas to the refinery, build out infrastructure to transport all that oil to the refinery plant, as well as establish a supply chain with inputs from all over the world. Then you have to hire the people, from Houston and the Middle East to build the knowledgebase to run the whole shebang, and none of these people want to live in Canada.
You're looking at an outlay of hundreds of billions just in startup capital, which would breakeven in probably 50 years. It's cheaper to build pipes or container it across the Pacific to send that crude to existing refineries.