Here's a translated relationship chart from the Ultinecia Omega guide. What do you think about it? I think that it makes the relationships between characters easier to understand.
http://www.ff7citadel.com/gameinfo/i...nia_charac.jpg
Edit: If it doesn't work, click on the link below, and click on Character Relationship Chart (FFVII Ultimania Omega) under FFVII encyclopedia.
The Final Fantasy VII Citadel: Game Information