Contrary to what a lot people might think they know from the movies, the X-Men universe stretches out quite a ways with lots of characters and lots of relationships. This super detailed relationship map for all X-Men characters from UncannyXmen shows just that.
Connections are color-coded to show the type of relationship between a pair of characters. For example, green is a one-sided infatuation, pink is a flirtation by both parties, and a dashed line signifies one of the characters is from an alternative reality. Wolverine sure gets around.