They Shift Blame On You
When you confront them about a simple problem you had in the relationship they suddenly become defensive and even start arguing with you for no particular reason. That can affect things negatively in any relationship.
They are constantly on edge and don’t want to talk to you about anything. Curiosity on your side is always met with hostility on their side. Doing this in a relationship is a real cliche when it is used time and time again.
One indication might be their childhood as is the case with similar situations in life. Maybe their parents didn’t treat them with respect and kindness or maybe they have trauma from a previous relationship. It can be very difficult to stay in a relationship with such a person.