I don't know, I think if I met someone who was a really horable, awful, mean, nasty, vile person, a low-life, moral-less, criminal who's mean to everyone and so on, I might be tempted to consider them a "waste of space". That's what I associate with that term, but I don't think I'm anything like that.

I do feel like I'm not a positive contributer like she is, I feel non-consiquential, invisable, would not be missed. I wouldn't use "waste of space" like this, but if she means it like this, it hurts because it backs up how I feal already.