If you find this hard, and it is for some people, realize that the other person probably finds it equally as difficult to be less forgetful and careless. Be more understanding and you will react more calmly. A covert subset of pain-causing questions are those that remind a person of painful situations and occurences. These forms of questions focus on improvement and not on complaints. They promote growth and positive feelings.
Quotes There is a sneaky technique of insulting others through the use of quotes.
People who use this method find it easy to mention heavier insults than usual. But I wouldn't say that to you. No subterfuge renders it permissible to insult people and cause them pain with words. Even if you are very subtle in your use of quotes and the person will only feel uncomfortable later on, it is still a violation of a Torah commandment. Quoting Aphorisms Aphorisms are short statements of wisdom which contain insights.