Universal. Some others here may say it is solely up to us to not be bored, but I relate well to your post. For along time I have tried hard to be involved in the good and fun things of life. Developed relationships, got engaged, started hunting and fishing, biking, sports, wieght training, botanical pursuits, naturalist pursuits, guitar and many others. I have enjoyed all of these but there always comes a point to which I realize that I really am not FULLY into any of these things. I can go far with my passions and then they subside. When my symptoms creep in I can temporarily toss any of these interests out the window. When I am feeling "normal" I am gungho, when I am off to dp/dr limbo land I lose alot of it, and this in turn drives my friends nuts. My interest is there but the detachment comes and goes. This is with people and things and activites alike. I am not saying I turn on and off, I am saying that these symptoms put a blanket over my enjoyment, participation and awareness.
Those I am with are gungho about all we do. I just want to go home many times. I blame this mostly on my dp/dr, and also I guess this low level depression that alot of seem to have. It is as if I try and know how to be happy but cannot get there without this "thing" holding me back from total engagement in what I am doing. Even exilerating things like climbing a moutian, when I get to the top I say "oh" that was neat and life goes on its dp/dr way. I have learned to live with this diminished sense of involvement and enjpyment, but it really astounds me to see people who truly are passionate and love life and have few boring moments. Boredom is huge in my life and is what has helped lead me to drink in the past.
And lonliness is the obvious result of all the above.
Even without symptoms it is hard to fully connect with something or someone as I see others do the same and want to do the same with me. But the times when I do connect, it is wonderful, and all in all I cannot complain too bad because there is so much to enjoy in life that even bits and pieces are worth it.