I'm not sure about your situation (married, kids, mortgage, etc?) but it's certainly do-able as a single person with a frugal mindset. I just finished up my first year at Mesa (obviously not one of the best paying regionals) and don't have a problem with making ends meet. However, I also caveat that with having no debt...car has been paid off for years, live with a roommate to cut costs, and limit my spending habits to a need basis. Also, I made sure back in my days training to always be able to pay for a lesson before I took it (thus ensuring, through two jobs nonetheless, that I'd at least not owe anything when I started starving as an instructor). Instructing was a challenge as we all know, but I just tightened the belt even more.
Just to give you a realistic snapshot of what first year pay is like (again, this is specific to Mesa): Normal line is around 85-90 hours per month...take away a few cancellations (no cancellation pay here...urrrrghh!!) and it usually comes out to around 80 or so. Assume 80 X $20.88 and generally around $350 for per diem (tax exempt!). So, a little over $2000 a month gross. Not a lot, for sure, but liveable if one's frugal with their spending. I try to avoid a lot of "going out" on overnights...beer and meals can add up in a hurry. Of course, every now and then I'll reward myself, but you really need to exercise self discipline (especially on first year pay!). I'm sure others (ExpressJet, etc with far better contracts) pull down better than that, so consider my example a "below average" indication.
Hope that helps in at least giving you an example of what first year pay can be. It kind of sucks, but we all know going in what it's going to be, so just plan ahead.
-Earl