Oh LegalLady ... That's MY story !!
I was paralyzed with fear about sharing at meetings ... I didn't have anything to say, I would be laughed at, I would sound stupid, etc. etc. I avoided discussion meetings as much as possible and never shared. I DID go to many speaker meetings which was a perfect place to hide until I was ready to talk. There came a time when I craved discussion meetings ... I still don't share at every meeting I attend but I no longer panic if called on. I also chair meetings ... which is a wonderful growing experience.
BTW - there is no 'rule' that says you MUST share ... it is OK to just want to listen ...