Just like in your personal life, some people at work may upset you because of the way they behave. Their behaviour may even cause you serious problems, such as stress, anxiety, or a loss of sleep.
You might even experience bullying in the workplace, and that can have a significant impact on your mental health.
This page from Mind explores ways of managing difficult working relationships, either with colleagues or managers. It also includes a section on what to do if you’re worried you’re being bullied.
There are many links to other organisations and sources of support, to help with both your mental wellbeing and the legal actions you might be able to take to protect yourself.