Dieting dynamics are interesting. When you are successfully controlling your weight, people around you often react in contradictory ways. Some become cheerleaders, celebrating each victory and reveling in your successes. Others try to test your resolve by tempting you with foods you are trying to limit.
Be firm. Tell everyone how important it is to you to lose weight and that having support will make your job easier. Friends who try to derail your eating plan may be jealous of your success. Interact with them less often for the time being. Good friends help, they don’t hinder.