Quebec thrives in a minority government. They control a large chunk of of the federal vote.
When there is a minority government, they can make demands to help the government pass legislature. They demand concessions in return for favortism.
Essentially it is holding the rest of Canada hostage which is what embitters many Canadians against Quebec.
As others have pointed out, they could not survive on their own. Frankly, Montreal would vote to stay in Canada and the Native lands would seperate from Quebec. For a province that demands cultural recognition, they have a horrible track record for respecting the native's rights.
The values of Quebec are at complete odds with the rest of Canada. Canada respects all cultures, visitors and nationalities. Quebec respects Quebec. As others have mentioned, visiting Quebec (with the exception of Montreal) is largely a negative experience. You are treated like a second class citizen and riddiculed in many establishments. Most maritimers, when visiting Ontario, will travel through the US just to avoid Quebec.
That is not a rich heritage, that is the attitude of a spoiled brat.
It doesn't make up all of Quebec's population, but hits a sufficient density that it reflects poorly on the province as a whole. I personally think that New Brunswick best represents Canada's French culture. They are mostly a fully bi-lingual province (thus an extremely high density of call centres) Signs are in french and english and the population are just as happy to talk to you in either language as well. They have their own culture, but are Canadians.
Each province has its own unique history and culture, it is the sum that makes Canada. It is a pity that many in Quebec seem to think their culture makes them superior to fellow countrymen and women.
Frankly I really hope they do seperate. Sometimes you don't realize what you have until you lose it.