It really is true that you have to believe in yourself or no one else will. Self belief is wrapped around self confidence, being grateful all the time, feeling love for others and for yourself, being positive, and having a soul full of "I believe in me!".
There is a great deal of negative energy floating around that wants us to believe that we cannot complete tasks or achieve any goals without the help of some guru or coach or mentor. While it is true that some people find it easier to achieve with that sort of help, they also find it easier to blame someone else if things go awry.
Today, sit down and have a talk with yourself. Talk about how you believe in you, and what you can do.