People who are in a toxic relationship are scared of leaving reasons best known to them; the particular one my friend gives is, "What if I meet someone worse than him?" You say what? That's known as "the devil you know is better than the angel you don't know" Then I would rephrase the statement and be like "What if you meet someone way better than him"

I said this in my blog when writing on this topic. The fear of meeting someone worse. What do you mean someone worse? You have seen worse already. The best you can do is walk out of the relationship and avoid traits like that in the next relationship, build boundaries, and let everyone know what they are doing. Like you said, people don't just walk into a toxic relationship; they weren't like that before until they ate the forbidden fruit.