I do not understand the question. What has holding apart have to do with the existence of individuated particulars? Is this a question about what is space?
I have given this description many times. There are things. Space is inferred from the relationship of things.
This may hinge on what is meant by “things” – objects of the mind or material objects.
In your description I understand that these are objects of the mind. And so things, galaxies, green, gods, virtue, running have equal value. And so I ask you how is it that green can equal when it requires a substance to exist? The answer I have received has been to give importance to the objects of the mind (the concepts) and to downplay the physical objects themselves.
All the while, I have not had an explanation of where these objects of the mind are derived from, only that what motivates the concepts themselves (namely, the physical objects) are unimportant. If the sense experience is so unnecessary then why not do away with the senses and sense experience?