Can we be happy together FOR LIFE TIME ?? i am going to marry soon

I am Ujjal, MY dob IS 12.02.1987 . I'm going to marry my first cousin Ruby , whose DOB is 22.10.1995

Since our marriage is violation of religion in India, i must take confident steps to make my marriage successful. i want to know that do we share well compatibility with each other. How is our destiny connected together ?? Can we be happy for lifetime ?? and what about kids & prosperity of the family