Fusion Mysteries

I have a Frage about Bismuth and Pearl. Do Du remember how Pearl jumped into Bismuth's arms? Well if they were happy to see each other shouldn't they have fused? The only thing that could not have made this fusion possible was if Bismuth was not happy. Maybe Bismuth was not happy because of what happened between her and Rose Quartz. (If Du watched to the end of the episode where Bismuth came in Du would understand.) I still have 2 Mehr questions. Why didn't Bismuth tell the Crystal Gems about what happened? Also, what did Rose Quartz tell the Crystal Gems about Bismuth's disappearance. Anyway I hope these made Du think a little.