Can't tell grandma

I came out to my parents and some friends some time ago, but I can´t get up the courage to tell my grandma. I´m so much closer to my grandma than I  am to my parents. I feel it´s harder to tell someone that you can´t ever fulfill their expectations if you love that person so much more than any other being. I know she will love me in the end, but it´s just so terribly hard to make the first step.