How do we marry as an Inter-Caste couple?

Inter-Caste couple trying to find a way to marry

I'm a 28 Year old Male, Muslim by religion but not a proper practicing one. Infact, I'm borderline atheist at this point. It's just for the sake of my family, society and relatives that I am not putting it out in open. I am in a relationship with my girlfriend from the last 8 years, She is a Hindu by religion and a fairly practicing one. She believes in god and loves her culture, her festivals and her family bonding over it. We started dating in our college and it was difficult to start with since we both knew there was no future. But since we could not resist, we thought of giving it a chance till we were in college, and planned of ending it as we left. But as expected, that did not happen, After our college we started long-distance for almost 3 years, And then came back to our cities and continued, At different stages, we decided to end it because we were getting emotionally attached deeper and deeper, We even mutually broke up around 3 times, but could not last for more than a week. So this part is clear that we don't see anyone else as a partner in life, Cannot imagine myself with anyone other than her.

Now coming to our families, Both conservative, but her family, especially her dad has a lot of hatred towards muslims due to political and social influence, It is to that extent that he insists the family to not buy meat from muslim shops (claiming they spit in it), don't make muslim friends, don't eat in muslim restaurants. My family does not hate hindus, but from a marriage pov, they want a Muslim girl to come into their house, Either a real, or a converted one, but she has to be eventually muslim. I am in no favour of converting her because myself Im not religious and I respect her thoughts and her family bonding.

Now the problem is, We thought of confessing it to our families a lot of times, I even did it to my mother, and after hearing about the whole story, she agreed that yes you can try, If she is not comfortable in our house, you both can live somewhere else, but even she is like at some point she has to accept islam. But when she got to know about here family's hatred towards muslims, she got scared for me, and said please don't get into this. Also she said don't let her confess, her parents will hate her for life and will marry her to anyone they find at the earliest.

She is not able to confess because she is very much confident that there is no chance whatsoever that her family will accept this. Even if I say I'm an atheist, we will live separate and she can follow her religion. She also feels her dad will go to any extent (even honor killing) to stop this and will throw her to any guy asap. We don't want to run away, as we both love our families and want to support them emotionally and Financially and don't want to give them a social stigma.

Now I don't understand what can be done ahead, they have started looking for arrange marriage rishtas for her, We are really helpless. If someone has a logical solution, advice, comment on this, Please help