My heart is getting weaker someone please advise me

Am in a relationship with a lady who does nothing to show that she is in a relationship with me. At first when we started the relationship she was all over me, she will call every short minute, something happened and we had a little score and after the score she had never been the girl i use to know. What should i do to her? should i dump her for another girl or what? the problem now is my Daddy know of our relationship he even called us and advise us and the love test here also proves marriage. but i think is not working out, my heart is weak i can't concentrate at work. someone here advise me