Buy this book.
The Psychology of Poker by Alan N. Schoonmaker, Ph.D.
Do all the worksheets at the end of each chapter.
Reevaluate how and why you play.
Adjust, and try again.
My guess is that you play too many hands and enjoy the "thrill" and/or the "action."
It is also possible that you play for other reasons. But when you finish the book, you'll have a better frame of reference for how to think about poker so you can make money at it.