Brinana,

. You can never rely on willpower, only on commitment. Make that commitment to yourself (tell someone, write it down, post it here), and then just do it. As others have said, start with getting rid of the junk food--Lillibeth has some other great ideas.
I have to not necessarily disagree, but I guess diverge from what others have said. Most of the time the cravings are gone, but at other times, I have them. And sometimes I do give in to them. The key for me is to not allow those times when I give in to become the norm. It's one meal or one day, but then I forgive myself and recommit to eating healthy. And I have to do that over and over again, and never let that one meal or day turn into more. I've gone two steps forward and one step back, but that always puts me ahead in the end.
You CAN do this!