Yes it is hard playing a shaman at times, alot of people don't realize you can heal. I've been through this in alot of games, but I just shrug it off and then go find a decent group
If agroup is going to keep me out because they don't think I can heal, well...I would probably end up dying very quickly in that group anyway because of them making other stupid mistakes. I'd rather group with someone that knows enough about the game to know that shaman are healers also.