Life is full of fake people. It is so easy to believe someone when they tell you exactly what you want to hear. When a person shows you who they really are, believe them the first time. Some people are only nice for their own convenience. You have to distance yourself from these people otherwise they will hang around as long as you let them. The type of people who only call when they need something or come around when it's beneficial to them.
Not everyone has your best interests at heart. Sometimes the one person you'd take a bullet for ends up being the one behind the gun.