yo dude, it's perfectly normal.
BUT u got to ask urself, "What are the consequences if i take the
wrong step?" Just imagine how disastrous it would be if u break ur
gf's trust. That would stoop your morals to a new low.
As u have said, ur gf is your best friend, is she replaceable? If
she's not, then u must reconsider your feelings and set it
right.
I have been in the same shoes as you before, so i hope that helps.
