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.
Perhaps as good a classification as any of the main types is that of the three lusts distinguished by traditional Christianity - the lust of knowledge the lust of sensation and the lust of power.