When you make the decision to change a habit or create a different lifestyle, be prepared for potentially negative feedback from some of your friends. Some people may think that your choice to change is a poor reflection on their choice to remain the same.
The best thing you can do is spend time with people who inspire you to make positive choices. When you surround yourself with peers who celebrate your success, it will encourage your continued progress. You could also make new friends. If your goal is to start running, join a beginner’s running group. If your goal is to eat better, you could start a recipe-sharing club.