Is it weird that I’m dating my cousin and am sexually active with him?

Okay, before you judge me, here me out please. So I went to my moms house in Africa, and my Step Fathers nephew came to live with us. I had never met him before, but found him very, very attractive. One thing led to another, and we fell in love. You don’t decide who you end up loving, it just happens, and it happened to be my step cousin. Is it wrong ? Mind you, my mom married my step dad but never had kids with him. I am the last of three children. I need Advice!!!!