I was forced to be a girl online for a year due to an ex friend of mine
That's interesting. What made you want to be a girl online?
I was desperate to get my friend back. And I felt that it might have been a way to achieve that.
You must really like your friend, but it's not a good idea to misrepresent yourself. How would posing as a girl get your friend back anyway?
That way she wouldn't suspect it was really me.
Pretending to be a girl will likely compound your problems. When your friend finds out that you've been pretending to be someone else in order to talk to them they'll be upset. A better approach would be to just be honest and talk to them about how much you miss them.