Just keep going! No diet that claims you will lose that much weight/size in such a short amount of time is worth your time. It takes hard work and patience, and there will be "mistakes" but we learn from them and keep going. It WILL BE worth it.
Things like practicing gratitude can be life-changing. It's those small lifestyle changes that can help you reach your goals in life. All it really takes is making a small shift, a small change in your daily routine to bring some positivity.