I'm sorry to hear this. Did your Dr. predict 8 months with or without chemo? If there is a Dr. that still believes you have a chance with more chemo, then why not give it a try? This is a personal choice and only you can decide but since you successfully responded to treatment before, who says you won't this time as well?
Obviosuly no one can make this decision for you, but I think the question for me would be, is the chemo only going to increase my chances by a couple of months or a couple of years and then ask yourself about the quality of life you would have and want during that time.