Oh, there've been books I feel that way, that I don't re-read as much right now. I used to read all the Narnia books, and the Lousia May Alcott series (both Little Women and subsequent books, and the Eight Cousins set).

But one that stays consistent comfort reading is Jane Eyre. Since I first read it in 7th grade, I re-read it at least once a year. So many wonderful things in that novel!