Is Eva sympathetic or unsympathetic?

Eva is quite a complex character, so it's inevitable that there are both sympathetic and unsympathetic elements to her personality. Much of what is good and bad in Eva stems from being left by her husband. All alone with three kids and no money, she shows herself to be a remarkably resourceful woman, doing everything she can to put food on the table. But her necessary toughness has a damaging effect upon her children.
Yet even here, her actions reveal the numerous paradoxes at the heart of her character. For instance, Eva saves the life of her son, Plum, only to kill him later. Though motivated by a desire to protect her son from the indignity of a drug-induced death, Eva subjects Plum to a particularly painful death of another kind: by burning. Later on, when Hannah herself catches fire, Eva immediately jumps out of the window and tries to put out the flames. And yet we're never actually sure of how she came to catch fire in the first place. Given what she did to Plum, we may well think that Eva had some kind of involvement.
Despite all this, there's little doubt that Eva is a remarkable character. Though often expressed in unconventional ways, it would appear that she does love her children and is indeed devoted to them. Throughout her long life, she repeatedly puts her family's needs ahead of her own, even going so far as to cut off her own leg—or so it is widely believed—in order to claim insurance money. Whether or not we agree with her methods, Eva shows that when all is said and done her family is the most important thing in the world to her. That in itself, one could argue, is an attitude deserving of our sympathy. How she goes about displaying that attitude, however, is somewhat less so.