Edna

 "I would give my life for my children; but I wouldn't give myself" (Ch. XVI)

I think what Edna means by that is that she is willing to give up her life, her physical being, to protect her children from the type of person that she is, so unyielding to societal roles and so uncaring about what she is supposed to be doing, but she couldn't live a long life being something other than who she is. To her, giving herself meant giving up her freedom and basically living the rest of her life in suppression of her true self and being depressed. If her every day was filled with being someone else and living with depression, I think it would be a type of torture. So forced to choose between being a shell of a person for her children or not being around, also for her children, she chose the latter.