Well, in the past, fighting spirit meant taking hits and continuing to rise and move forward. I wound up battling an entire garage full of men b/c of bias and chauvinism. I remember crying almost every day when I could get alone - it was that abusive and horrible. I stayed put out of sheer belligerence and stood down the opposition. It was hell, and even now, I'm not sure it was worth the toll on my health and sanity. I just couldn't let them beat me. At the time, it was THE most important thing, expecting them to ultimately take me down but taking as many of them with me as I could.
My fighting spirit is pretty much trampled these days though, wrestling with illness will do that.