You start by changing the things you think are holding you back. You mentioned that you are fat. Okay so what are you doing about that? Are you eating healthier, exercising, taking vitamins? How are you working to better yourself?

Just from your post I see that you have a negative attitude. How many people do you see hanging out with Winnie the Pooh vs. Eyore? You are the the Eyore in that statement.

People don't like to be with complainers. They avoid them because their attitudes are toxic. People like to be with achievers, doers, happy, friendly, active, people.

Start by looking within yourself. That is what needs to change, not the world around you.