Coworkers are like family as we spend most of our day, every week, sitting next to and communicating on some level with our coworkers. Most coworkers are excellent and easy to get along with. However, there are some who are not so easy to get along with and the more you talk with them the worse it will get. Those trouble workers should be politely dismissed and ignored for greater workplace health.
Most people are contributors through their positive personalities and mature disposition. They can hold a reasonable conversation and seek to treat people appropriately. They can create the most enjoyable workplace as reasonably possible and want positive relationships with others.
When you are surrounded with positive people the workplace will be enjoyable. You will be more motivated to come and engage in meaningful work. The workplace is only partly about the work and more so about how you feel and interact with others at work.
Toxic people poison everyone around them and should be avoided at all costs. They have a negative outlook on life and won't contribute anything of real value to you or the workplace. By being polite but also firm you can maintain your boundaries with them. Avoid getting into non-work related discussions with them.
With all relationships consistency has value. Consistency in your personality will draw positive people and detract from the motivation from negative people. When someone is seeking advantages at the expense of others they look for personalities that don't seem to be confident or change based on the circumstances.