Welcome to the site, and I'm glad you found your way to the chat room. I hope we can help you out. There are a lot of anti-depressants to try, so if one isn't working within a few months it's time to switch to another one. You may want to be sure to see a specialist in this area, and try therapy as well. I highly recommend CBT=Cognitive Behavioral Therapy. It teaches you a way to think about you, your spot in life, your illness, etc etc etc. Everyone can benefite from this type of therapy.
Is your lupus out of control as well and your physical health state contributing to the depression? There are many options for treatment, and sometimes a second opinion is in order if it's been 3 years and you aren't much better by this point.
Welcome again - you've found a great place for information and support. We understand... (((hugs))) Hang in there - it will get better at some point.