Reasons why your dog moves when you sit next to it
Below are a number of possible reasons why your dog has been doing it and what would make them more likely.
The cause might be that it is intimidated. This would be more likely if it moves away when you have gotten angry recently but it does not move away when you are calm with it. In this case, it would help to be calm with it and to use positive reinforcement training to get it to behave the way you want.
The cause might be that it is allowing you to have the more dominant position in the room due to seeing you as the leader. This would be more likely if it immediately goes to sit in a lower down position.
It might also be the case that it has learned that the behavior gets rewarded. If you tend to give it things such as toys, treats, or extra attention, when it moves away from you, it will likely do it more in order to get more rewards.
Another possible cause is that it does not want to be bothered while it is resting. This would be more likely if it immediately goes to a spot where it can sleep and if it only does it when it seems to be tired.
Dogs can also become depressed and it might be why yours has been moving away from you. This would be more likely if it started doing it since an event might have caused it to become depressed and if it has not been showing much interest or excitement around you or anyone else at all. You can read more about dog depression here.
Below are some things to consider when figuring out the main reason why your dog has been doing it.
If your dog did not always move when you used to sit next to it, it would help to consider what else happened when it first started doing it. If it started doing it suddenly, it could be due to things such as learning that the behavior is rewarded or because it started getting intimidated.
If your dog does not always move, when you sit next to it, it would also help to consider what is different when it does not move. For example, if it only moves when it is sleeping, it might be the case that it does it because it does not want to be bothered.
Why do dogs sit facing away from you?
It is a sign of trust. Your dog is trying to tell you that it isn’t going to attack you and it is showing you this by keeping its teeth as far away from you as possible. It is also making itself vulnerable to you, showing you that it trusts you. … That being said, most dogs simply like to be scratched in this area.
Why does my dog put his paw on me?
If your dog puts his paw on you, it can be his way of saying I love you. We pet our dogs to show our love and affection. … Your dog could be insecure and seeking your attention, a sign that you should show him a little extra love. It could also be that your dog is trying to communicate that he’s hungry.
14 Signs Your Dog Doesn’t Love You (Even if You Think They Do)
Many dogs dislike being touched or patted on the top of the head. All it takes is a quick search on the internet to see countless photos of dogs showing stressed body language while being patted on the head. Body language signals your dog might exhibit are ducking away, lowering of the head, stepping away, putting the ears back, licking lips, or whale eye (whites of eyes visible).
Humans seem to be disposed to want to pat a dog on the head; this is likely for several reasons. A dog’s head is usually the closest part of the dog we can reach. For some dogs, we don’t even have to bend down to reach our dog’s head. Humans seem to mimic this behavior from other humans. Think of a parent lovingly stroking their child’s hair. Children may enjoy this, but most dogs do not.
Humans can also be quite rough when patting a dog on the head, and it may not be an enjoyable experience for your dog. Coupled with the fact that dogs inherently dislike something reaching down from above toward them, most dogs quickly learn to associate a hand reaching toward their head with discomfort or stress. This leads many dogs to become head shy, and they learn to duck out of the way of a hand reaching toward them. 
This can be an annoyance when you have to follow your dog across the room to put on his leash, or even downright dangerous if you need to grab your dog in an emergency and he ducks away from you.
But the good news is there are many things that you can do to prevent head shyness and even give your dog a positive association with someone reaching toward his head.