My cousin has been trying to get disability for 4 years but a friend of mine got it in just a year. You have to apply and apply and apply and you get denied a lot, even if the doctor says you need it.
I'm going to try to get on disability this year sometime. I was told I needed it by a doctor but I have to do all the paper work and then a bunch of other crap before they can either accept or deny it. I don't know details since I myself have not yet gone through it, and I don't know how different it is in Canada.