With so many students at UT, it’s quite possible you could go DAYS without even seeing your friends. In addition, you’ll grow and make new friends whether you go to UT or Rice.
It won’t be like going from your small middle school to a big high school, because in high school some students already know each other and you have to break into the groups. At Rice, everybody will start from scratch. People won’t know each other, many students will come from far away, and you’ll all be together on the same boat. 
Well, in the same dorms and residential colleges. 
In addition, you can always attend UT for graduate school, but that financial aid package to Rice is once-in-a-lifetime.
Go back to Rice, spend a day there, try to imagine yourself there.