Nailit - the effectiveness of group courses like the one you describe is very patchy, and isn't so much a reflection on the philosophy of 'talking cures' as on the capabilities of the group leader as a teacher, and the group dynamics.
One of the well-known phenomena in the sector is 'therapy junkies' who just adore coming to such groups.
Another element that has distorted its perceived benefit is well described by others here - namely when organisations buy a course and build it into staff evaluations. I attended one such course as part of a compulsory organisational training package, which issued 'life coach' certificates to some very untrustorthy and manipulative people.
It sounds like you've had a duff experience this time round, but I'd urge you not to chuck out the baby with the bathwater.
Finding trustworthy people you can talk through your problems with is something that everyone can benefit from. The danger is that without it you might try unconsciously to substitute something else for it, like shopping (mentioned above), alcohol etc
So follow your heart and your instincts, but try not to cut yourself off from possible sources of help.
And as others have said, if you haven't found benefit from this group leader then your written feedback on the course is a valuable way of making sure its better in future.