I bet you are a wonderful person and don't know it. Can you see a counselor? They can help you improve your self esteem. There are also self help books on self esteem. You can also work on just writing down affirmations about 10 2-3 times a day to boost your mood and self esteem. For example say positive things about your self or good things that happened to you that day. Like I felt happy, I was hugged, I am intelligent , I was kissed, I saw a beautiful flower what ever makes you feel good at that moment. But you could have anxiety which may require medication The best thing is to talk to a professional or someone you trust. Biofeedback that helps with breathing and the fight and flight response to lower anxiety may help and also acupuncture may help and mediation.