My heart goes out to you. BUT, have you seen your ticker?

You've lost 20 lbs! That is a HUGE ACCOMPLISHMENT that a snicker bar cannot wipe out.
Please focus on all the hard work you have accomplished. Drink a lot of water and eat clean the rest of the day.
You can do this because you already have done this.
I'll bet that most of us here have gone through the same feelings of despair when it comes to poor food choices.
Then, reflect back and ask yourself why you really had that snicker's bar. Is it because you didn't have anything else? Is it because you wanted something sweet? Maybe next time, you could make a healthy smoothie? Think about how that snickers bar made you feel. Focus on what you could do next time instead. Finally, take all the junk out of your home and replace it with health food options.
Be good to yourself and treat yourself the way you would treat a good friend. We usually put ourselves lats on the list and we bash ourselves for our mistakes, rather than treating ourselves with the kindness we deserve. You deserve some kindness.
I hope you feel better soon.