"One's-self" keywords

There are some keywords which include the phrase "one's-self", such as:

looking-at-one's-self-in-a-mirror (708 titles)
talking-to-one's-self-in-a-mirror (106 titles)
talking-to-one's-self (81 titles)

There seems to be little justification for this spelling, so isn't "oneself" better?

There is also this one, what do you think this means?

crossing-one's-self (43 titles)

"The two-word phrase one’s self is only justifiable when self is used in a spiritual, philosophical, or psychological sense. In all other cases, one’s self can be replaced with the pronoun oneself."
-- http://grammarist.com/spelling/oneself-ones-self/