Rights

I was in a relationship from the last 4.5 yrs approx. The girl propose me firstly n I accept her proposal. By the passage of time our relationship got stronger and it was long distance relationship although we were from same home town, it was due to study. As I was doing CMA from delhi and she started doing B.tech from Allahabad. Later on one day I ask for her marriage but I made my intention clear to her that after that I will not marry to anyone else and she agreed the same then we do the same. After that we got in physical relationship many times. When I visited Allahabad we use to stay in hotel. And when she visited to Delhi for summer training, I arrange her accommodation in my building and we use to sleep together for approx 2.5 month until her training get over. She also visited to my older brother flat which is in Chattarpur, Delhi, he lived with her wife. We both belong to different caste She belong to Pandit and I from Baniya. In my family there is no caste or even religion from in respect to marriage but in her family caste is a big problem although they are well educated. Now the problem is she is denying from marriage. I don't have marriage pics. I have only some pics in which she had used Sindoor on her forhead and the hotel in which we use to stay there we mentioned Husband- Wife in relationship column and we had same father name which is mine father. Currently we both are in Delhi and working in different companies. What are my rights in this case?