It's the usage of "distance" in verb form. "distance oneself from a person or thing." It means feel less friendly or positive toward the person or thing, which means 疏远 in Chinese. So in this case, I think the author omitted "from you" after "distance themselves." And that made you confused. Hope it will help.

"Sharing this with your coworkers may cause them to instinctively distance themselves" Sharing this with your coworkers (Noun clause - works like a noun), may cause (verb), them (object), to distance themselves (reflexive verb). So here we have: Subject Verb Object Reflexive Verb (I think... lol) It is like saying: Fire (Noun) causes (verb) bombs (object) to explode (verb). So in this case: Something (Noun clause) causes (verb) the coworkers (object) to do something (verb). However, if the action of the last verb is done by the subject/object of the verb, then the verb might be reflexive and include himself, herself, themselves, myself, etc. I shot myself. (The verb "shot" is done by the subject and to the subject) The coworks distance themselves (The verb "distance" is done by the coworkers and to the coworkers. So putting it all together: We have a noun clause (Sharing this with your coworkers) causes (verb) them (object) to distance (a reflexive verb that is done by the object and to the object) themselves (reflexive pronoun that accompanies a reflexive verb). This might not make any sense to you, and I might be explaining it a bit incorrectly, but the point of it all is: Noun ---> verb----> (if the verb is done by the noun and to the noun, then add reflexive pronoun: himself, herself, myself, themselves etc). Hope this helps in some way! Feel free to ask questions I might be able explain it a bit better or in a different way!

Thomas has a good answer It should be "distance themselves from you" but some words have been omitted. "Sharing this with your coworkers may cause them to instinctively distance themselves" --> Sharing this with your coworkers may cause them to [[stop paying attention to you]]