Intercaste love marriage and dilemma of approval from Uncle

Hi... I am 22 years old n doing my post graduation.. My boyfriend is 29 years old and is a businessman.. He belongs to khatri family and I belong to rajput family.. We are in a serious relationship from last 3 years.. When my parents got to know about it they totally got so much angry... My mother died last year.. My father is my only guardian... My parents also had love marriage... They also faced many difficulties.. But just because they both were rajput they have a reason to give me... The major problem is that my boyfriend's maternal granny was from Muslim religion but she married a Hindu guy... So obviously she became Hindu... But my father and my father's elder brother are opposed to it as they believe that my boyfriend belongs to Muslim background but his whole paternal and maternal family is Hindu.. Another problem is that my elder cousin ( sister) is still unmarried.. Daughter of my uncle.. My father is not ready to think about my marriage before her.. But my boyfriend's parents remains very sick and need a daughter in law to look after them... His age is also passing... M in a big trouble... There is not much tym... No one is understanding... My father likes my boyfriend as he is of good n moral character but can't do anything without his elder brother's permission... We have tried a lot but in vain.. Please help me

You are not alone facing such difficulty. There are always so many reasons for parents to oppose LOVE MARRIAGE. I know its been hard for you to face all this but if you see your father's side, he is also in very big dilemma. In your case there just too many issues:
ie. Age difference, Caste issue, Girl Family Issue, Ill parents of Boyfriend and more over a dominating Uncle.

But brighter side is that your boyfriend is settled as you said he is a businessman as well as your father likes him. My suggestion is that marry with your boyfriend with your father's permission privately or secretly (legal marriage) so that your boyfriend can assure them they have a daughter-in-law, however go for traditional marriage only when your cousin get married. It will solve lots of problem but will again create few like - you can't bear child unless you are formally married, you can't be with your father-in-law / mother all the time. I think your bodyfriend can manage a nurse for his parents meanwhile.

Later on when your cousin is married, your father can just emotionally get his brother (your uncle ) to get married you as per your wish.