Don't be afraid to fail. Don't waste energy trying to cover up failure. Learn from your failures and go on to the next challenge. It's OK to fail. If you're not failing you're not growing.
While I have felt lonely many times in my life the oddest feeling of all was after my mother Lucille died. My father had already died but I always had some attachment to our big family while she was alive. It seems strange to say now that I felt so lonely yet I did.