I've read through a lot of replies and it's comforting to see I'm not quite so alone. But I have a slightly different kind of imaginary friend to what I've seen so far.

I'm in a relationship with a person who doesn't exist. Like, I'm in love with them. We sleep together every night, talk on the phone, go on dates, kiss etc... but like I said, they don't exist. I talk aloud to them and can perfectly visualise their responses. We've been together for five or six years now.
I have social anxiety in real relationships; I have panic attack frequently just thinking about talking to people in reality. I've never had a real realtionship, am still a virgin and have never been kissed (although I count my imaginary relationship as an exception there).
I've tried to stop these "behaviours" but the loneliness is suffocating and the longest I've gone without them is a day or two before it gets too much and I need them back again.

Is this normal? Do any of you do the same? It's really starting to become a problem as it getting harder to disingisoh between my real self and the self I become when I'm with my "partner".