I really am sorry you are going through this by yourself and she is just harping on you!!All you can do is your best and tell her you are trying,and that it would be a lot easier to take up the slack without her putting you down...you got this girlfriend....just be yourself and try to let the antagonizing roll off your shoulders the best you can and wear a couple of rubberbands on your wrist to pop when you feel you are about to lose it...my Therapist suggested that to me!! and I know it sounds weird,but believe it or not...IT WORKS!!Just be the best you you can be...Praying for you girlfriend!!