I have a similar problem... We have a drummer that shows up when he wants to... I play EVERY Sunday, 2 or 3 services in one day, and this cat don't come to rehearsal, Sunday skool, Bible study... nothing. ALL musicians have to go to classes, and this cat just come and go when he pleases. I am the 'Lead' drummer... and whatever goes on in that corner in my responsibilty... In that situartion, it was on me to tell that bro that he was coming incorrect...
If I could do it again, I would take the advise from mr_c32005, talk to the pastor. He can't help if he don't know. Don't let your emotions tell you what to do, pray on it, take it to the pastor, and the situation will get taken care of...
In my situation, this person stopped coming to church cause he didn't want to go to classes. But the pastor reinforced the 'rules' of being a musician...