CAPRI ~ I think it starts with one tiny baby step: one after the other -- that adds up to a good day; then one good day plus another equals a good week, and so on ...
First, you need a PLAN: write it down; what you are going to do and eat tomorrow; include exercise and activities. Then get your journal and calendar out, and tick them off one by one; these accomplishements each day will make you feel good about yourself.
Second, write down a page of positive affirmations about yourself; you know and I know that you have many good qualities -- whenever the neggies come a knockin' ... counteract them with your positive statements; and read them OUT LOUD! Keep doing this until you believe them; that may take months, but it doesn't matter how long -- until what you see catches up with them. ie I am a good person; kind person; fair person; gifted person; artistic; smart; successful; and so on ... YOU ARE MORE THAN THE SUM OF YOUR WEIGHT!!!
Third, use the power of distraction: Journal your thoughts; listen to positive music; watch positive shows; read a positive book; go for a walk; clean your house; sing a song, phone somebody, etc. Keep busy and come here; this is a great place to get your mind focused on something else; especially your new journey towards healthy living ...
This is just a start; and these are just tools, but they can get you where you want to be ... you can do this!