As you know, the Pattersons used to attend parties on a regular basis in the first few years of the strip but this facet of their lives slowly but surely disappeared. By 1985 at the latest, John and Elly preferred staying home to going out; this is, of course, because John finally noticed the crippling social phobia that plagues Elly. The strip that was reprints on 13 September 2009 pretty much highlighted the fact that she simply does not seem to mix well when she's not in a dominant-or-equal social position to those around her; she can't seem to work up the courage to talk to other people unless she's the center of attention so she ends up in a corner feeling like an afterthought. John, who did mix well, picked up on this as time went by and started coming up with reasons why they should just stay home. This was, of course, inspired by enlightened self-interest; he wanted to minimize her resentfulness so as to make his life easier.