I agree with most of the previous posters. It's fine to want to fly out of Toronto (both to support Canadian carriers and frankly for less hassle), but it's just so expensive.
We're doing a trip to Florida in October, just the two of us. Flights out of Toronto were over $1200 total (these were picking the cheapest flights available), whereas the Southwest flights we booked out of Buffalo were $490 total (and honestly, that's because we're flying out in the afternoon; had we been willing to do early morning, we could have got them for $400). Even with the price of gas, it's still a huge savings. And parking in Buffalo for the week appears to be pricing out cheaper than parking at Pearson (or cabbing), so that's an additional savings.
Unfortunately, as was mentioned, not everyone has that luxury of flying out of the States. My sister and her husband are meeting us in FL and flying out of Newfoundland. It would have easily cost them $2000 (thank goodness they have one of the flights free on rewards miles).
I read the budget and transportation boards here and I really do feel for the people in the States who are having their travel prices go up. However it's hard to be too sympathetic to people having to pay $200 round trip (all in!!) and saying "I guess we're being priced out of travel" when I'm worried about getting home for Christmas because AC and WJ want $1900+.
Let's keep our fingers crossed for some sort of solution!