Couldn't find anything on this anywhere on the net so I thought I'd ask here.

I have an imaginary girlfriend. In essence she's what I'd consider the perfect girl, you know, the person you would go with if they existed. I find myself pretending to cuddle up to her at night, I find myself having whole conversations with her all the time (though usually in my head, though occasionally i find myself whispering it). I am fully aware that she doesnt exist, it's not like I actually see her or believe she's real, but it is worrying me a lot. I'm pretty sure its some kind of way of dealing with the fact that I cant ever get myself into a relationship or get girls to even look in my direction (low self esteem doesnt help), but I feel like its getting out of control. Any help or suggestions?