I think it's terrific that you are still breastfeeding! You don't need to worry about her starving herself because she is getting nutrients from you. Nursing past 6 months of age is right on par with the recommendations of the American Academy of Pediatricians and the World Health Organization. Keep nursing!
This is probably just a phase and won't last forever. It could be teething, yes, and it could be illness, but you know your child best of all...please don't be scared by someone diagnosing an illness over the computer!!!
Does she have teeth? My son wasn't interested in really eating food (other than a few taster bites) until he had a few teeth. In ancient cultures this was seen as a sign that the digestive tract was ready for solid foods.