Can I break off with the legacy that was set in our family regarding relationships?

My elder siblings all have one relationship and end up marrying the person they are in relationship with. I fell in love with someone whom I thought has all the qualities that I want from a guy only to find out lately that he is not what he profess to be. He has shown signs of irresponsibility and utter words that are not acceptable. Aside from this, he is not resourceful and accuse me of being demanding. He said I have to accept for what he is. I also resent having mentioned to him about our family's legarcy. Can you help me on this?