I am muslim, he is hindu. How do I stop myself from falling for him.?

I am not allowed to marry someone who is not my religion, he is my brother’s friend, we have gone on outings with a group, I have joined the company where he works. He is super nice to me. Says hi in front of everyone and after every hour checks on me if I am doing okay and talks to me, eventhough he sits very far from my desk. He has a good position in this company  
I don’t understand if he is really nice to me or he is just doing bcz I am his friend’s sister. Also I really like him and when he talks to other girls I feel jealous.  

I told him yesterday I was out of my bus tickets and he bought a ticket for me.  
I am day dreaming about him I know its impossible we cant be together I am in trouble I dont know what to do. 🙁
What should I do to stop my feelings?