To change your attitude: try to think of things you like about yourself. Make a list, and every day add something. You need to have confidence and start liking yourself before any one else will. Your posts in this thread are dripping with self-loathing. You call yourself so many names. Stop being so mean to yourself and treat yourself better. Treat yourself like your worth something and others will see you the same way.

Hope that helps some and hope you can find some comfort, if not happiness.