When is it time to quit trying to feed?

my lo is 2 weeks old and i am not trying to quit now but she lost 11% of her body weight because i am not producing enough milk. now i supplement her night feedings to make it easier on both of us and to help her gain weight but the lactation consultant is against that. i can't let my baby starve though. i have received help from 2 lactation consultants and am scheduled to continue to see one of them but i am a single mom, no family or friends to help us and feeding is beginning to feel really stressful and selfish of me because it isn't helping her if it's not enough to give her what she needs.