Is it possible to split yourself off completely from the 'shared reality' and create a whole different world to live in? R.
With nonphysical travel you can experience a wide range of realities, even ones you create yourself. However your physical reality will still remain, as it is a teaching reality and it is one that you agreed to experience for a certain period of time. Physical reality has some limitations, as you know, especially as far as what is capable and what is not. The shared reality is much stronger in physical reality, so you have to deal with more overlapping from other people's creations into your own. In an out of body travel or even while you sleep, you immerse yourself in other realities where your consciousness is much more free. You can learn to enhance these skills like OBE, dream manipulation, and travel meditation to use them to explore these other realms and even create in them. These other explorations may give you some rest from the normal demands of physical reality.
As far as physical reality, there is much you can do to reshape it and create it more to your liking. Your personal reality is really your own personal creating space. It is where the shared reality is the least. Here you can have much freedom in creating. Problem is most people do not know how they create their world in the first place, so their own personal reality creating space in physical reality is a mess from bad reality creating and from others.
As your reality creating skills grow so does this personal space. Then other elements start to become more under your influence. I can not go as far as to say that you can control other people with your personal reality creating space, but surely they will be affected by what you create there, especially if it is in harmony with the universe. Everyone seeks this harmony on an inner level and when someone is able to create such harmony, people tend to enjoy being around that reality and will even transform to a higher standard while they are affected by it.
At one time churches were built on energy vortexes. The reason being, energy and reality creation is much enhanced in these places. Putting churches in these places enabled the priests to create a much more separate and hopefully peaceful reality within physical reality, so that the common folk could connect with God and also experience peace and serenity. The priests of these times understood how thought and action created the environment, especially where the church sat. So much of the practice they did was to help foster this energy and create a bubble reality where it would seem the woes of physical life were much reduced.