My daughter is refusing the breast and she is nearly eight months old. She doesn't have a cold and appears to be well. My son was an avid breastfeeder at this age and I weaned him at two years old. It was a real battle to get my son to wean. I am sure that if he had had his own way he would have weaned very late.
I think she is having a nursing strike. Surely its unheard of for an eight month old baby to self wean.