I've recently been working with many people who want to improve their health and get in better shape. As they have sent in their "before" pictures, most of them have made negative comments about how embarrassed they are of their current condition. I can definitely relate to how they feel from past experience. It is easy to be critical of our bodies when we are focusing on our imperfections, but it is important to remember that you have been blessed with an amazing body that is more complex than any computer or machine, and is much more valuable than any structure ever built by man.
There may be some things we have no control over in life, but there are many that we do. If you are suffering from ailments brought on by excess weight or poor diet, you can do something about it. Our bodies are very forgiving and resilient and by adopting healthy habits we can begin to condition our bodies and improve our health. Even the most out of shape person should be grateful for the ability to walk, talk, move, and perform basic functions. You might be categorized as morbidly obese, but at least you have legs. There are many people who were born with birth defects or who have lost limbs. It is inspiring to see how some people overcome this type of adversity.
I think it is important to develop a proper respect and appreciation for your body, regardless of the shape you are currently in. Your body really is a temple so treat it like one.