To be 'sick of' something means to be extremely tired frustrated or exasperated by something. When you are 'sick of' something you are fed up angry or bored with it. You can be 'sick and tired of' something 'sick to the death' of something or 'sick to the back teeth' all of these expressions are interchangeable and informal and used to say that you have had enough.

1. Harry is sick to death of his roommates' poor behaviour. They are just too noisy and messy so he's going to have to move out.
2. I am sick to the back teeth of this weather. Does it ever stop raining here?
3. I liked that song at first, but I've heard it so many times now that I've become sick to death of it.

1. I'm sick and tired of having to work such long hours for so little pay. I need to speak to my boss about getting a raise.
2. I am sick of being underappreciated in my role, nobody recognises how much I do around here.
3. I am sick to death of our competition stealing our ideas. It's time to take action.