I can understand your feelings. I have also gone through with this kind of feelings. When you love someone then you can not think your life without him or her. But another person having the same feelings for you is not sure. When you realize this truth then it is very difficult to accept this.
In your case I feel that your boy friend has not that much feelings as you. If this is so then he will not take the step to leave you. He is not going to fight with his parents for you. And you should also not involve in any relation which has foundation of anger of parents.
Reading above lines are painful. I know but currently you are thinking from your heart not from your mind.How you believe a person who leave you just for wrong thinking. He knows you, your character, your personality then why he is not able to convince his mother? In this case basic thinking is wrong. Think what will happen if his mother will not accept you after marriage? Then you have to struggle a lot.
Believe me, as time passes your sad thinking and memories with this boy will fade. I have experienced this.
I was in Delhi, I loved a girl of my neighbor. She also liked me. We have spent too much time. Later on one fine day she got another rich boy. Suddenly she stopped talking me. I have seen her that she went with that boy in night. I talked her but she flatly told me that she is not interested in me. One plain sentence. I know that she is not good, still I was not able to stop thinking about her. I spent too many sleepless night. Wept a lot, but later I decided that I will not involve with her. As time passed I came out with this sadness. After 1 year she called me I repeat the same sentence to her which she told me.
Now I came forward with this situation. So believe me you will also. Think from your mind not from your heart. In any case I am with you to help.