First of all, you have to tell yourself and believe that you are worth it, that you deserve to be healthier and to treat yourself with love and self-respect so that giving up the unhealthy behaviours is not a deprivation but an act of self-love.
Do it now and do it every day. You are worth it. You are an incredibly valuable person. Recognize it and accept that you deserve better.
Secondly, you have to stop beating yourself up for past behaviours, including unhealthy habits you practiced today. Today is now in the past and it cannot hurt you any more. Berating yourself for past failures and past bad practices is a total waste of mental and physical energy and it gets in the way of the new perspective you are about to adopt with respect to yourself. Negative attitudes towards the self go against being able to correctly evaluate your worth.
So, today you didn't exercise and you ate crap. So what? Join the club. I ate potato chips yesterday and the fattening nachos my husband made for himself and I haven't done my weight training I had listed to do today. Well, hell!! Is the world about to end? Am I suddenly that much unhealthier than I was yesterday? Do I care?
You and I, we are works in progress. Nothing gets achieved in just a day, or even a week, as far as making major life changes and health improvements. These things start off slowly, gather momentum until they become daily, fixed habits and before you know it, you are healthier and happier and it didn't make you go through hell to achieve it. Do not think you can create a brilliant diet plan in just one day, or become super fit in two. You need long term goals and short term, daily and weekly goals to help you achieve the big ones, in baby steps. You can be healthier, and you can like yourself more, but I think the liking yourself more and knowing that you are worth it must come first.
Thirdly, get rid of horrid old notions like "dieting." Never does anyone any good. Instead think, "eating more healthily." This, you can do, and it 'aint rocket science. Diets just make us resentful and stubborn and rebellious because they make us give uo tons of things we like and make us feel deprived. What is key is to devise a way of viewing food as fuel and nutrition not as emotional pacifier, and devise a way of eating that you can maintain for life, not just until you have dropped "X" pounds. Thereare books out there that address the issue of emotional eating. Go get one or two and read them, be honest with yourself and start working on that now. You have anxieties that go beyond your shape, like this paper, and they send you straight to the cookies and crap food that poisons your system and makes you even more unhappy. Maybe a therapist could help resolve some of these issues?
How to eat for life? Divide your plate up into sections and fill each section with certain type of food at every meal. A carbohydrate, like rice, potato, bread, etc: a protein, meat, fish, pulses, dairy, etc; several helpings of vegetables of different colours so you get a wide variety of vitamins. You will have to be strict about certain things and give up certain things. You cannot expect to be healthy, energetic and happy with yourself if you choose to dose/anaesthetize yourself with candy, cake, donuts, cokes, etc. These have to be limited. Once you can learn to view them as occasional, treat foods, you will actually start to feel better because your brain chemistry will become more balanced as you lose your dependency on these pollutants. The old food pyramid really isn't such a bad idea.
You need to tell yourself that you deserve better than a breakfast of Twinkies, a lunch of Doritoes and a macDonalds for dinner. You really do, hell, everybody does! You deserve fruits and vegetables, a bowl of oatmeal, a lentil burger, a bowl of fruit and yoghurt, etc.
Spend a couple of weeks just getting your nutrition under control before you attempt to make any other changes. Then, tackle your fitness goals and get to it. Decide how much time you have and when to exercise. Write these times into your daily and weekly planner as fixed appointments with yourself and they are inviolable. This is your time, no-one gets to interfere with it. Guard this time with your life and don't surrender it unless circumstances force you to, at least not in the beginning, until the exercise too becomes a habit.
Start off slowly and gradually. Make loose goals to begin with. Like, I vow to do three cardio workouts this week. Do this for a couple of weeks until you start to feel stronger. Then, start to vary the types of cardio you do, so that you target different muscles and keep things interesting. Then, after a couple more weeks, introduce weight training/resistance work. If you read up on what exercise does for you, and believe me, the list of benefits of cardiovascular exercise and resistance training is a mile long, you will start to see why you are so deserving of having regular exercise in your life. You deserve to lower your risk of getting cancer. You deserve to increase your longevity. You deserve a well functioning metabolism. You deserve strong, healthy bones. You deserve the natural anti-depressant effects of exercise. You are so worth it.
What you need to do to start listening to yourself and keep listening and to act upon what your brain and body tell you, is to change the tape going through your head. You don't think you are a worthwhile person, the tape going through your head tells you this over and over again. This is where you have to start. Change the tape. Replace it with one full of more positive messages. No-one is all that bad! No-one is a total failure and who said failure is so bad anyway? Failure and crewing up are what make us human and help us to fight towards creating better things.
Get yourself a book on building self-esteem and make sure it has chapters on how to stop the negative thoughts and replace them with healthier ones. OK? Do this first.
The very fact that you have come here for help and advice says so much: that you recognize your need to get out of this bad place and into a healthier one. It's a great start. Now, tell yourself, just like the L'Oreal ads, "I am worth it." And start something new tomorrow.
Wishing you all the best,
Clare