Stuck in a dead end job

Hi,

I've been in the same job for eight years without possibility of advancement. I've never really liked this job, but it pays rent and I've had yearly raises, I have seniority. I've been sucking it up for 8 years. I feel mostly comfortable with the people at work. I know all the internal games and know how to maneuver them. I don't want to start all of this over again in a new workplace. I'm tired, bored, and less productive. I've told my boss and HR rep that I want to do something else, they say they're listening, but I've been waiting 2-3 years with false promises, they always have other fires to extinguish. I've applied for another job in the same workplace, but it's not something I really want to do. I don't think I'd like any other job anyway be it in the same company or elsewhere. I don't want to work in my field of studies. On the other hand, I have a great workmate, and we have fun and we cheer each other up. Sometimes my workmate is overwhelmed as well. I've been crying at home, at work. My workmate is encouraging me to change jobs. I love my workmate, but I don't want to burden her with eveything I'm feeling. I'm schizophrenic and know I should strive for stability, but I'm miserable. I don't want to change four quarters for a dollar. Some days are good, some bad. I can't reason myself. How am I going to be able to do this job another 30 years? I feel depressed, anxious, stressed, worried, sad, more so in the past few months. I'm not suicidal, though life has seemed unapealing since diagnosed with schizophrenia 15 years ago. I have many hobbies, but they don't seem to counter all the bad in my life. I don't have friends outside of work. I don't have social encounters outside of work. I'm a hermit, I'm an introvert. Talking one on one with a therapist makes me uncomfortable, my mind becomes blank and I don't know what to say or what to respond to questions. As they like to tell me, I have to look inward and I will find all the answers, but it's not helping me in the now.