How do I get my name off a Mortgage?

A while back i was hurting finacially, and so were my folks. They were in the process of Refinacing there house, and the broker asked if I could be on the mortgage as well, since I was living there at the time. I agreed to is because it paid a lof of Debt that I had. over the course of 5 years I paid my parents off and then some, but I am still on the Mortgage. I have great credit score, and no debt, except for my parents house. Its hard to get a loan now because they say i have high debt to income ratio because of this. What can I do to get off my parents mortgage, since I have not lived there for 3 years.