The stress of school and getting into an internship is insane.What are my options?I'm this close to, guess?

Basically i've been studying nonstop my entire college career, I have a BA is Psych with a GPA of 3.5(which will get me nowhere) and right now i got accepted into graduate school for nutrition. I'm trying to be a dietition and the internship requires that i take prerequisites. So i'm taking A&P in the summer, but it's killing me. All i do is study, and even worse i don't get the grades i deserve. right now i'm borderlining on a b- to a c+. The Internship requires that i have to get high grades to be competitive, but working this hard, not getting the grades i deserve and not having any time socially(no girlfriend in 10 years, see my friends once every two weeks) and constant panic attacks, is life really worth it. Next week i have three finals in a row for one class, already studied for them, but it's not enough. I'm passionate about nutrition, but am i just too stupid, should i just off myself becuase my life isn't worth living at this point, is my future that dim because of the choices i made in terms of my major?