Loss of appetite is one of the common symptoms of Lupus, as well as nausea and diarrhea. It is not uncommon to suffer some weight loss as a result of these symptoms. In fact, half of all patients with lupus have a loss of appetite (anorexia), which results in weight loss. This is usually noted in the early stages of lupus, anorexia & weight loss are associated with the amount of disease activity.
Systemic Lupus Erythematosus or SLE is a chronic (long lasting) disease that causes chronic inflammation in tissues, joints and organs. This is caused by an autoimmune dysfunction (autoimmune means immune activity directed against the self). What happens in Lupus is that abnormal antibodies are produced in your body and these antibodies cause the inflammation.
This is what your doctor meant when she said you body is attacking itself. The immune system fights the body itself (Auto=self). In autoimmune diseases such as Lupus, the immune system makes a mistake and reacts to the body's own tissues and attacks them causing inflammation, pain, and all of the other symptoms of Lupus.
The immune system is designed to protect and defend the body from foreign intruders (bacteria, viruses). You can think of it like a security system for your body. It contains several different types of cells, some of which function like "security guards" and are constantly on patrol looking for any foreign invaders. When they spot one, they take action, and eliminate the intruder. In lupus, for some reason that is still not known or understood, the immune system loses its ability to tell the difference between a foreign intruder and a person's own normal tissues and cells. So, in essence, the "Security Guards" make a mistake, and they mistakenly identify the person's own normal cells as foreign (antigens), and then take action to eliminate them. Part of their response is to bring antibodies to the site that then attach to antigens (anything that the immune system recognizes as non-self or foreign) and form immune complexes. These immune complexes help to set in motion a series of events that result in inflammation at the site (tissues, joints, organs). These immune complexes may travel through the circulation (blood) and lodge in distant tissues and cause inflammation there.
Inflamation is a protective process our body uses when tissues are injured. Inflammation helps to eliminate a foreign body or organism (virus, bacteria) and prevents further injury. Signs of inflammation include; swelling, redness, pain and warmth. If the signs of inflammation are long lasting, as they are in lupus, then damage to the tissues can occur and normal function of tissues, joints and organs are impaired. This is why the treatment of lupus is aimed at reducing the inflammation.
I hope I've answered your questions. Please let us know if you need anything further!
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