I think I've lost my only friend. Should I just let him go?

Lay off for a little while. Act like you totally aren't interested when he texts you. Spend some time with yourself. Learn to enjoy your own company. Do things that you like to do, whatever they may be. You will be amazed how quickly he will change his tune, trust me. In the mean time, put yourself out there. Make more friends. Better friends who will be there for you and understand what you are going through and try to help you through it. You are so worth it, trust me.