I have been trough this from the other side. Our SUPERB singer, a woman with CARISMA, you know, you look at her and feel something tingle and then she starts to sing and you feel testosterone rushing towards the brain... sigh... what a loss... yet she told us "guys, it was a nice time, but its time I have a change, I will leave you towards the end of the year." It was okay. We came over it, no bad blood. One has to accept this. And we still make music, even without having replacement. We just changed style a little. And if we hadn't overcome it we wouldn't have been worth it - for a band is not just background to one member, but everyone gives his part to create the whole thing.