My coworker is always complaining about work and is really negative. How can I deal with this?

Have a talk with him on his unhappiness at the work place maybe you will inspire him to remove this negative mindset

You’re the average of all the people who surround you. Take a look around and make sure you’re in the right surroundings.

But of course its not so simple to distance yourself from a co-worker, especially if the both of you are tasked with working on a project together.

Ultimately, you should not let the negativity affect you. True, it is easier said than done. Here are some ways that you can consider to deal with it:

1. SET BOUNDARIES

Only engage this co-worker only when you need to (ie. discussing work), and distance yourself when this co-worker is looking to chit-chat (read: massively complaining and being negative about work)

2. BE UPFRONT

However, if you do indeed care for this co-worker as a friend, you could be honest with him/her and talk about how the complaining and negativity is not only bad for himself/herself, but also to his peers. You never know, you could be the positive force and turn things around. It probably will take some time though.