I have a quote from Mahatma Ghandi that has been very helpful to me, so here it is for you!

"Man often becomes what he believes himself to be.  If I keep on saying to myself that I cannot do a certain thing, it is possible that I may end up really becoming incapable of doing it.  On the contrary, if I have the belief that I can do it, I shall surely acquire the capacity to do it even if I may not have it at the beginning."  -Mahatma Ghandi