Yellow, I have no practical advice for you since I am not from Canada. I only want to say that you have been through a lot at such a young age, and I admire your strength and fortitude.
I urge you to contact as many employment agencies as possible, put your needs to them, and make your enthusiasm and skills clear - you have ms and you can't work full time, but that does not mean you cant work or be productive within certain constraints. However, if you work part time, just check that it wont compromise your disability payments and make you worse off.
As for treatment - I agree with Lyndacarol - each must make a decision as to what they think is best for themselves. If Tysabri is best for you, contact your national health doctor - Canada must have some sort of health insurance for people who cant pay for treatment themselves. Also the company who makes the drug may have a programme to help people like yourself ( I believe Biogen are part owners).
My message is only that I wish you well, I really do