Other fields (listed in alphabetical order) that study human behaviour include: anthropology, criminology/ criminal justice, economics (especially micro-economics), education, marketing (sometimes listed under business administration), neuroscience (sometimes called bio-psychology), and sociology.
Two other options:
(1) Major in psychology, but don't tell your parents.
(2) Major in another field, but also major or minor in psychology. Again, don't tell your parents. (If they somehow find out you are taking a psychology course, simply tell them that you have to as part of your major in ____ [field other than psychology].)
Finally, some other things to consider:
"COLLEGE EXPOSED: What Majors Are Most Popular, Highest Paying And Most Likely To Get You A Job"
http://www.businessinsider.com/best-col ... udy-2011-6
Good luck with whatever you end up studying. 