Stressed and afraid. With my cousin?

I have previously asked a question and also got a answer but the doctor who answered my question had assumed my family member will understand me but in reality the opposite will happen.My main consern is my family members who will do there best to ruin my life. I am a orphan, live in my aunts house like a all time servent from 2008(though now a have somewhat better position than before),I am in love with my first cousin and want to marry him(a final year engineering student).We don't have enough time in our hand so in first few years most likely I have to be with my family members who are not flexible by nature and will never accept our relationship(we will try our level best to approach them).And for new job it may happen that in that difficult situation my cousin will not be able to be in the same place with me.So what kind of mindset I need to have to be with those difficult people all the time while not getting in touch with my cousin? I am afraid but want to overcome. Plz help