Puzzled

I'm on the pursuit of happiness...but I seem to be stuck at a brick wall. You see sometimes I think my life will be much better with someone by my side. A significant other to share my life with ...soo then I start my process with a guy I meet or have had my eye on and it never fails thatt I am let down. So then I think things are just less complicated... But then I cannt help but feel that something is missing...that I'm missing a piece.... Where's the missing piece to my puzzle ?