There is an understanding in any job that you will not get along with everyone. Sometimes it is your boss or it can be someone that is a vendor for your company. Sometimes you're the boss and the person you clash with is a subordinate. Regardless of who it is the worst thing that can happen is letting that personal concern become a professional disaster.
Authors are, in a large way, solo employees but there are many that we come into contact with during the course of writing and publication of even just one of our books. We may sit for hours at a time in the solitude of our minds but depending on your proficiency with various aspects of the process you will still utilize the expertise of beta readers, editors, cover artists, and a formatter. There are also bloggers and marketing PAs you might get in contact with. Not to mention the people that will help you out and you will have to work hand in hand with if you do any online or live events for the release and follow up when the book is published.
We also network with other authors. It is one of the best and yet most difficult things we do in promotion of our work. Some of my closest friends have come from these networking moments and I have learned more than I ever thought possible. The difficult part comes when an author acts unprofessionally or does something that makes you lose respect for them or their work. It would be easy to say just walk away or work with someone new but what if you already have a connection or partnership with them? What if have or had plans to work on something together but they do not hold up their end of the work? How do you move forward when you are stuck waiting on them?
What do you do if the person you have worked with is acting in a way that not only represents them as unprofessional but because you are or have been connected with them it brings your reputation down as well? Again, it seems easy to say not to get mixed up with people like that but it can take a long time to find out they will behave that way. Protecting yourself is vital in any profession. It is heartbreaking to have to make the choice between someone you have worked with and moving forward without them but if you do it in a professional and unemotionally charged way hopefully you can both keep your reputations in tact and simply go on to bigger and better things separately.