You say that you know it's not "the truth", but are still looking for approval and permission from the elders to miss meetings? Why? This is an organization that publishes accounts of brothers in Africa who walk miles and cross alligator infested rivers to get to the Kingdom Hall, why would you imagine the elders, who have no education or training in mental illness, are ever going to give you permission to miss meetings due to mental health issues? They have been trained to believe that their are no good reasons to miss the meetings.
I believe this religion is toxic to sensitive, guilt prone individuals. Instead of looking for approval from the elders, work on freeing yourself from Watchtower induced guilt, the elders only have the power that you give them.
I highly recommend meditation, it has been very helpful to me.