I guess it's partly about whether you have the time and inclination to be a parent/teacher/mentor to an eighteen year old who proving to be a liability

or

whether you want to get on with making music with your band.

Put another way, is it more important to protect her from reality or to protect the band from her influence?

Of course it's easy to be rational from this remove, but to me it looks like a case of pull chain to flush and move on.