I can totally relate to this. This feeling of "wanting to be sick" is one of the biggest obstacles for me when I'm trying to recover from my eating disorder. I've been dealing with it for many years, but I've never been anorexic, which makes me feel like my ED isn't real. I think the reason behind this for me is that I want attention and to be taken care of. I really wanted to be hositalized and not having to worry about school or work or social stuff, just let others take care of me. It's the same thing with many physical illnesses for me. A few years back my sister had her appendix removed and that was so hard for me. I couldn't visit her at the hospital because I got anxiety attacks. The memories of how some of my family members sat there with her all day and bought her things and made sure she had everything she wanted still hurt. No one has ever cared about me like that even though I have several mental health disorders. I guess I've always been too high functioning and none of my illnesses have been visible to others, so no one's really understood how sick I actually am.