Join Date: Jun 2008
Location: SJ Newfoundland, Canada
This sounds like anxiety.
The anxiety is only getting worse too because every time the people come over he gets punished (made to leave the room, outside by himself). In order to get him calm around your friends, you need to make it a positive experience. This will require your friends cooperation.
When they come over, everybody should take a quick walk or go on the back porch. This will help Murt feel included with the company. Then have someone play with him, preferably everybody should. Once he's good and tired you can sit down for your movie, treats can be given as he behaves. It's up to you to decide what is his appropriate behavior, if you don't want him on the couch with your friends then start training him to not go on the couch ANY TIME.
Putting him outside does not solve the problem, it only makes it so you cannot hear or see him. For a dog getting older you need to make some concessions. As my dog aged I needed to adjust to his changing behaviour too. It got to the point where his anxiety did not allow me to participate in keeping guests downstairs (ie, my roommates house parties) because my dog freaked out and vomited on my bed.
You want to start addressing the problem now. I say start with including him in your meetings. If you cannot calm him down by making him tired then you can start investing in herbal remedies such as a thundershirt and some rescue remedy.