For a short version of my question - why wasn't there significant separatist sentiment among French Canadians outside of Quebec, particularly in Ontario? Despite French language and culture being neglected to an even greater degree in English-speaking Canada, there doesn't seem to have been an equivalent separatist/terrorist movement among French speakers outside Quebec. Is my view of this correct, and if so, why was this the case?
For a longer version of my question - though I'm American, my mother comes from a French-Canadian family in northern Ontario (Timmins and Sudbury, specifically). The town she grew up in had a very large French-speaking community, and my grandfather was very active in various societies and groups that promoted French language and culture. Despite all of that, my mother said that there wasn't any separatist sentiment among the French population of her area, and viewed the Quebecois separatist movement as distinct. She also believes that this feeling was mutual - she went to university in Quebec at around the height of the student separatist movements, and recalled that despite being French-Canadian and speaking primarily French, she was often mocked by other students as "l'anglais" (the englishman") because she was from Ontario
There's always more to be said but in the meantime you may find answers about some of the early roots of the English-French divide in Canada in this thread by u/enygma9753. You would need to be familiar with the fall of New France and the situation the British authorities found themselves in after the 1759 conquest of Quebec, which the thread above outlines.
The historical English-French duality in Canada is central to Canadians' own perceptions of nationhood and cannot be easily described to non-Canadians (or even Canadians themselves) without a lot of context and an appreciation of some of the nuances in French Canada's complex evolution.
In the aftermath of the American Revolution, some 60-80,000 Loyalist refugees migrated to other British colonies, mostly to Canada. They were English-speaking and fiercely Protestant and many were reluctant to settle in Quebec, where the Catholic faith was tolerated. Most went to Maritimes as they were closest to New England. Quebec at this time included much of eastern and southern Ontario along the St Lawrence River-Great Lakes corridor, which was sparsely settled then. Loyalists began to move there (present-day Ontario) too, where the French Catholic population was smaller. Tensions inevitably emerged and Britain was compelled in 1791 to divide Quebec into two parts: Lower Canada (now Quebec), where the Catholic faith and French civil code had accommodations; and Upper Canada (Ontario), where British law and the Protestant faith were paramount.
It would be best to see French-Canadians as a collection of several different regional groups of francophones, not one monolithic group. Franco-Ontarians would have a slightly different experience historically and culturally than those in Quebec, the Acadians of the Maritimes, or the francophones in western Canada. Even linguistically there would be some differences between regions.
Quebec has been and likely always will be regarded in an existential sense as the heart and soul (culturally, historically etc) of French North America, as it was the only province where French Canadians remained the majority and its struggle to maintain a unique francophone identity amid a majority anglophone N. American population of some 350 million (Canada and US) was most pronounced. One interpretation is that the Quebecois view their cultural and linguistic identity as under siege since 1759 under British, and later, Canadian administration. English Canada's attempts to dominate and/or assimilate the local Quebec population happened in peaks and valleys throughout Quebec's history and is too complicated to get into in one thread.
In modern times, the Quiet Revolution in the 1960s -- a profound cultural and social awakening that transformed Quebec -- changed the concept of francophone identity in the province from one based on the Catholic faith to one more focused on secular values. Language rights still remained paramount, and esp. important in provinces where francophones were in the minority and their rights were seen as eroding. Quebec is often seen by francophones in other provinces as the defender of French minority language rights in Canada.
Quebec separatism (another extremely complex topic that can't be easily dissected in a single thread) is but one expression of this desire to protect and defend French culture and identity in Canada. There are those who are quite happy with the status quo, where Quebec has an enhanced presence within Canada due to its unique culture and as the second largest province population-wise. There are others in Quebec who feel that Canadian confederation hasn't protected the francophone identity enough and the only way to do that is through separation -- either through an EU-style sovereignty association, or unilateral independence at the extreme end. The FLQ's terror campaign from the 1960s to the 1970 Crisis was a violent, militant expression of this.
The popularity of separatism has ebbed and flowed over the decades, culminating in a razor-thin 51%-49% Quebec referendum vote in 1995 to reject separation and in favour of remaining in Canada. The losing Premier of Quebec then, Jacques Parizeau, blamed the loss on "money and the ethnic vote", putting the blame on culturally diverse anglophones in Montreal and the impression/theory that the federal government had bought its way to victory. This controversial remark likely harmed the movement politically for years, though many hardcore separatists agreed with the sentiment.
The Quebec separatist cause has been on the wane in recent years, but as past history has shown, English Canada would be naive and even foolish to think that the matter is settled for good. The fallout of Wolfe's victory in Quebec still looms large in an existential sense in Canada to this day.