Have you thought about volunteering somewhere once or twice a week after work? You may or may not make friends while doing this, but either way you will have helped someone, and that feels good. I am certain that you have many gifts to offer the world - you just need to find an outlet for them. Also, a daily gratitude practice can help. Write down three things you are thankful for when you wake up, and three more at the end of the day. Even small things matter - such as, I am thankful for my morning coffee or I am thankful I can hear the birds singing outside today. Try to find different things to be thankful for. Also - Buddhist philosophy can be very helpful. Staying in the moment and noticing your thought patterns is the first step in changing them. Also - the book "Taming Your Gremlin" was helpful for me - to notice that negative voice. Hugs.