I've had some people in my life who didn't bring any positive changes. My ex was one of them; he only focused on his “cool” past and complained about everything happening in the present.

Some people I met were also concentrated on themselves and their past and told about their fears — and did nothing to change the situation. Also, being credulous about all non-science. I definitely can call them toxic, because their life and views impact me when we communicate. And we tend to be like people we use to communicate. Someone says we can distract from this, but this is b*t, we are like people who are close to us.

I can't afford myself to spend energy on someone who pulls me down, I don't have it much.
So, I often evaluate whether I gain more positive experiences from a friendship than negative ones. If someone disturbs my peace, I make the decision to cut them off.
Something should happen to these people to change, such as some stress or disaster, and they should want to change. Because even if you love and help a lot, they only become more complaining because actually they are OK with such life.

It was very hard for me to cut off people like this because I don't have many people at all. But if I do not do this, there will be no place in my life for someone else.

Also, I had a best friend who did this to me 2 times. She lacked the energy for our friendship, and I realize now that I must have been toxic for her as well. I believed she was my best friend, but she didn't invite me to her wedding and behaved like at a distance. She didn’t have the courage or empathy to express that she needed space; instead, she just started ignoring me. And returned in 3 years. And after a year again, went ignoring. It was extremely painful — she was my only girl-friend.

If she supports you, it's a lot. But IMHO, receiving support from someone who makes you feel bad at the same time is like help from the demon — works but tricky.
I think every person deserves a chance (especially someone who we know for a long). But in order to be strong and independent, I cut off ties that bother me and cry into my pillow