Don't announce to your friends that you are on LumaSlim Reviewa diet or trying to lose weight. This may encourage some of your friends to subconsciously sabotage your efforts. Your weight loss plan is not everyone else's business.
You'll always have some friends who are toxic to any kind of healthy living. Most of your friends won't be like that, but figure out which ones are toxic. Spend more time with your friends who don't tempt you than with those that do.
Just because you are at a bar with your friends doesn't mean you have to get drunk, or drink any alcohol at all. It's fine to order club soda with lime and drink that all night. Unless you make a big deal out of it, everyone will assume you are drinking a gin and tonic. They won't have any idea that you are avoiding all the empty calories that booze has to offer.