I think the crashes are server based in some way, like it gets over-loaded at points. It doesn't happen as much as you would think, though. As for the group disbanding, go with what xRubyx said, that works for me.
Also on what Alette said; my friend was complaining about somehow being in someones character yesterday, nice to know that shes not the only one glitching like that xD but if that glitch happened, best thing to do is just wait to be back in your character again, I'd guess.