How to get dog to be on his own..?

I've got a one year old golden. He's very mellow and always has been. I work from home and have young kids. My spouse also works from home a bit, so someone is pretty much always here.

The dog is obsessed with me and only me. He follows me around all day and sits at the door if I don't let him in the office.

I walk the dog daily. We have lots of toys. The kids will throw a ball or play tug of war with him, but if I'm not in the same space, he just doesn't want to engage with them. For example, we have a big fenced backyard. If the kids are out there, the dog will only reluctantly join them. He'd prefer to be with me. If I'm in the backyard, the dog is running zoomies, chasing the ball, rolling in the grass - just having a great time on his own.

I've got the kids now feeding him. One of the kids is training him a little. The kids will play with him. I just can't seem to get him unglued from me.

He can be left home alone and doesn't cause any problems. He doesn't sleep with us (we actually have him sleep in another room), he's crate trained. I purposely lock him out of the office a few times a day just so he can spend a little time away from me. I also will put him outside and shut the door. Most of the time, he'll just sit at the door and wait to come back in. When he thinks I'm going in the office, he now races me to get in there first before I shut him out. I'm at the point where I'm just trying to not engage with him much in hopes that he'll latch on to someone else.

The only thing I do with the dog that nobody else does is walk him. Kids are too small to walk him and spouse doesn't want to. Other than that, I'm trying to pass all caregiver duties to the kids. Help! I just need some space and he needs some exercise besides his daily walk with me. He's an absolute angel of a dog except for this!