Ready To Give It up

My husband & I argue constantly. I am no longer happy being with him. We've only been married for 16 months & I feel terrible about it. I feel like everything changed after we got married. I'm starting to resent him & it's horrible. He is such a sweet person & I feel like I'm the worst wife in the world. I know he deserves some one better. I don't believe in divorce but I have no idea what to do at this point. I just don't want to live the rest of my life unhappy. I need advice so badly please.