A separate listing for caregivers to vent is a great idea and would probably be a a link I would not visit. I am the patient and it's true that sometimes I become a little offended with caregivers venting about their horrible lot. I know it's not easy being a caregiver, but they will go on while the story is different for us patients.
The only problem I see with this is the wealth of information we receive from caregivers. They are often the ones to do the research and have suggestions on what to do to improve our quality of life. I would hate to have a caregivers' only forum where they answered questions, exchanged ideas and felt very free to slam the patient when he/she is becoming hard to deal with.
If it could be a place to just vent on how difficult it is to be a caregiver and not exchange care-giving information, that would be great! Just not sure how that can happen. I personally would not want to loose the information I obtain from caregivers.