He gets very distressed and barks incessantly when anyone leaves the house. Even the jingle of keys or when you stand up and put a jacket on sets him off. He also won’t go for a walk unless at least 2 people in the house go with him. The only exception is my dad who he will walk alone with.
He’s just never content unless everyone is at home. Are there any ways we can help him to get used to being separated for periods of time?
Start by leaving him in other rooms, start slowly by going out of the room for just a few seconds and build up until you can leave him for an hour or more. This is critical; do not immediately make a fuss of him when you get back, just ignore him like it’s normal.
If you can do leaving the room, set up a pet cam or baby monitor (baby monitors are always going cheap online), go outside out of view , maybe drive around the block and wait, eventually he will stop barking, and if possible get back and come in before he starts up again. Again do not make a fuss. Get a drink put your stuff away and after a few minutes you can sit down, relax, and fuss.
It can take months to train a really anxious dog to self soothe, good luck.
All this plus: As we were getting ready to leave we’d invite our dog to get comfortable in a place he felt safe. Then we’d pet him so he’d relax and we’d say goodbye. In general he did well with hand signals so we’d also wave goodbye. He’d give us a look like he really wanted to go with us but would accept that this wasn’t going to happen. On our return he’d be happy to see us but not stressed.