Support is important when you are doing just about anything in your life.
Career changes, getting married, having children, going back to school, or making a big decision. Why shouldn't you have support when starting a new diet, health, & exercise lifestyle?
Don't expect to wake up one day and change everything about what you eat, and how much you exercise without a having recruiting the support of those around you. You need to sit down with your family & friends and tell them what you are going to do to live healthier and ask for their support.
If they truly want to support you, they will see how serious you are about your new lifestyle, about your goals, dreams, wants and needs and they will support you.
Those who can't or don't know how to support you, are usually the ones that don't understand your need or want to live healthier. It's not your job to to change their minds. Only know that you will need those who DO support you that much more.
If you really have people in your life that can't support what you're doing for you health, and have a way of bringing you down, then you have to find a way to put a healthy distance between you two.
Find support, someone who is going to call you, email you, text you, praise you, encourage you, cheer you on, and be there for you every step of the way!