How can I maintain a respectful relationship with my roommate who follows a different faith than me?

I am in a fix regarding the matter that I am an engineering university student and I am currently availing facility of hostel all was going well till my roommate offered prayer her method of offering salah was different but I do not paid much attention to this because in college I am in friendship with a Shia girl whose method also differed from mine a bit. I do not discussed this with anyone but I was told by my other hostel mates that she is a Agha Khani this made me furious. After that day I did not made her feel but I stopped using her things but I never stopped sharing mine with her. Now the problem is that we hostel mates of our batch make tea together and she is also included by us as we do not want to made her feel miserable I refused her not to make tea for me twice. Now, the question is that how should I behave with her as we have to share room and I have to live with her for a large span of time. And also we used to eat our lunch and dinner in same plate is this appropriate. Also give references to your answers sir. I will be very thankful if you help me to get out of this fix.