I agree with everyone else: take the meds! I can understand as a psych major and a person that has dealed with depression (because of being in a wheelchair for years, though I'm out of it now) why you don't want to take them.
I had a friend that pledged a sorority (the one I'm COBing in the fall) last fall, and she ended up having a mental/emotional breakdown because she didn't take her meds and didn't want her sisters to know about her problems. She thought the Prozac she was taking made her too bubbly and hyper (which it did sometimes, but it wasn't noticable). So, because of it all, she had to drop out of school and of course had to depledge. She was a great wonderful girl when she was taking her meds, but turned into a depressed wreck of a woman when she was trying to be "normal" around her sisters. Now she can't be a part of the sisterhood, and regrets it to this day.
Don't miss out on things like she did. Tell your sisters, even if just one or two of them. They will most likely find you responsible and trusting if you care about yourself enough to let them know and take your medication. Hope this has inspired you at least a little bit.