I seem to spend an inordinate amount of time putting out fires between singer and guitarist in more than one band. Always talking folk back from the ledge.
It must be tough on a lead guitarist when audiences focus so fully on the vocalist when they (the guitarist) believe themselves the most charismatic, important member of the band.
Add to that the simple fact that the drummer doesn't care if the guitar is there or not and the bass player is effortlessly the coolest guy/gal in the room, and you can see how that inflated ego gets so easily bruised.
They then lash out. Drummer shrugs, bass player sighs, singer bites.