Talking to them feels like a chore

Unless you're in a business environment or professional setting, talking to someone shouldn't feel like work.

Talking to someone in your life should be easy and effortless. You should never feel like it's an obligation or a job to talk to someone.

You act differently around them, and in a negative way

I've been in many situations where I realize that i act like a different person around somebody specific, and when I say that i mean like a bitter or more irritable person; someone I don't like being.

Others should bring out the best in you, and even if they aren't meaning to, if you feel like a worse person around them, it's time to take a step back.

You're mental state becomes worse around them

your mental health is very important, you should take care of it. Part of doing so is realizing when you're putting yourself in a bad place.

If you notice you're more depressed and sad when talking to a certain person, realize that and take some space. Remember, above all, you should be your own number 1 priority.

You fight a lot

arguments can be healthy at times, but fighting isn't healthy. Notice if you seem to yell at each other a lot, or if you seem to disagree about everything and very passionately so.

If this applies to you, you are putting yourself in a toxic situation which you should avoid doing at all costs.