For many affiliations, particularly political ones, your affiliation is more based on hating the outgroup than loving the ingroup. For example, I would wager that most Republicans hate Democrats more than they love Republicans and more progressives hate conservatives more than they love progressives. You need look no further than left and right leaning news sources to see this. A left leaning news source is far more about exposing people on the right than talking about how good the left is, and vice versa.