LGBT- friends 'joking' about me being in the closet?

I am an 18 year old female who has eventually come to terms with her uality. Two of my friends who are also s know this. I am in the process of attempting to 'come out' but it isn't as easy as I thought. My two friends are constantly leaving sarcastic comments on my Facebook such ad 'out of Narnia yet?' 'when are you coming out?' at first I found it funny but now due to the fact I'm desperate to come out & really struggling to do it I'm finding it extremely frustrating & as if they are just taking the piss. Help? What are your opinions?