Hey there, I know it’s painful and it hurts to be lonely. You can work on your self esteem to get over not feeling good about yourself. As far as loneliness and losing friends is concerned, the best thing about friends is that they always welcome you back and if not, you can make new friends or find a great friend in yourself. As far as your existential crisis is concerned, I’m sure all feels empty and worthless right now but you know you will eventually find your answers. A Counselor can help you with your self esteem and existential crisis. Please consult one.