Lack of confidence usually begins when we focus on everyone else. When you go about the business of comparing yourself to others, you get into big trouble for a couple of reasons. One, you don't know everything about the other person, so you can't judge them in a fair manner. Two, everyone is different, with different skill sets, talents and gives. You are trying to compare apples with oranges.
My suggestion is to STOP looking at other people to compare. Forget about what we all look like on the outside - the real jewel is inside. That includes you. You said you are smart. That's a jewell. You said you have different thoughts on subjects - well, guess what? That's a jewell because most people are too lazy to form their own idea and opinion about things.
Once you realize that the real worth of a person lies within, then remember that the eyes are a window to see inside. Take a peek at their eyes to find the beauty in them. Let them take a peek at your inner beauty. When you have eye contact, along with a smile - your inner beauty is revealed. You become warm and approachable.
If you look at someone with intent to compare - it is revealed through your eyes and you cannot see their inner beauty and they can't see yours.
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