The worst part is that the writers were just cherry picking which situations were ok for Picard to be involved with when it came to Worf.
Worf chose Picard as his cha'DIch yet when it came time for Worf to pull the plug on his own life he went to Riker. I think it's pretty clear they didn't want to have to put Picard in that kind of situation.
I think they gave that role to Riker so he could go to Picard and Picard could have the father-confessor role. It would be unlikely to have Picard have the moral soul-searching since he's the one whose supposed to have all the answers... unless he goes to Guinan to fulfil that role.