relationship communication?

[yeaaaaaaaaa]

my girlfriend of 1+ year and i met at business school. we are in the same program but have vastly different interests and backgrounds. she likes a lot of finance and i like an variety of things but whenever i mention certain business classes and/or the professors it as if she scoffs at them, like anything without numbers is insignificant because it lacks tangible metrics. as a result, i have stopped talking about certain things around her because i dont want to be demeaned, even though she doesnt target me specifically.

i have an interview tomorrow and the only people i told were a career office advisor and a girl who interned at the company last year, yet my girlfriend called me earlier to wish me good luck tomorrow and to implicitly ask why she had to hear about something in my life through a 3rd party (she did not name the culprit) rather than me feeling comfortable enough to tell her things directly. i tried to explain i didnt think it was significant until at least i was offered a position but i dont think she was buying it since she responded that she will now not update me on her prospects even when i ask her. how can i mend this situation?
obviously she is pissed becuase she is learning of happenings in her boyfriend's life from people other than her boyfriend.