Article in English: " A person will continue to manipulate you as long as you allow him to. You need to say "no" to protect your well being. Look in the mirror and practice saying, "No, I cannot help you with that," or, "No, that isn't going to work for me." You must stand up for yourself, and you deserve to be treated with respect.   You should not feel guilty about saying "no."  It is your right to do so. You can politely say no. When a manipulator asks you to do something, try: "I'd love to, but I'm too busy in the upcoming months," or, "Thanks for asking, but no." The manipulator who finds everything unfair and falls to pieces, they are attempting to gain your sympathy in order to use it to further their own needs. In this case, the manipulator will rely on a sense of "helplessness" and will seek financial, emotional, or other forms of help from you. Look out for attitudes and comments like, "You are the only one I have," and "I have no one else to talk to," etc. You are not obligated or equipped to meet this person's needs all of the time. If the person says, "I have no one else to talk to," try countering with concrete examples: "Remember yesterday when Grace came over to talk to you all afternoon? And Sally's said she's more than happy to listen over the phone whenever you need a sounding board. I'm happy to talk to you for the next five minutes but after that, I have an appointment I cannot miss." The manipulator will try to make you feel inadequate.  Remember that you are being manipulated to feel bad about yourself, and you are not the problem. When you begin to feel bad about yourself, recognize what is happening and put your feelings in check.  Ask yourself, "Is the person treating me with respect?" "Does this person have reasonable requests and expectations of me?" "Is this a one-sided relationship?" "Do I feel good about myself in this relationship?" If the answer to these questions is "no," the manipulator is likely the problem in the relationship, not you. Manipulators often twist and distort facts to make...

Summary in Vietnamese:
Biết rằng bạn có quyền từ chối. Vạch ra ranh giới. Tránh tự trách mình. Quyết đoán. Lắng nghe bản thân mình. Cắt đứt sự quy kết để khiến bạn day dứt. Chuyển sự tập trung sang kẻ thao túng. Không quyết định vội vã. Thiết lập hệ thống hỗ trợ. Tránh xa kẻ thao túng.