It's possible that your girlfriend is mad at you, but it's also possible that she's going through something tough that has nothing to do with you. Either way, if you are getting negative feelings from her, don't push her to talk right away. Give her some time to cool down. This will also give you time to think through your own feelings. Has your girlfriend's behaviour actually changed toward you? Is it possible that you're feeling depressed or anxious about something, and that you're imagining that her behaviour is worse than normal?  It's possible that she has always been a bit cold toward you, but that as the relationship gets older, you are realizing that you don't like the way she behaves. Have you been through anything difficult recently? Maybe you've been demanding more attention from her lately, and she's having a hard time meeting your needs, which has resulted in her pulling away. She may be ignoring you, but if she's struggling with depression, she might not even realize it.  Signs of depression include difficulties concentrating and making decisions; fatigue; feelings of helplessness, hopelessness, and/or worthlessness; insomnia or excessive sleeping; irritability; loss of interest in pleasurable activities such as sex or date nights; overeating or loss of appetite; anxiety; suicidal thoughts and/or destructive behaviour.  If you think your girlfriend might be depressed, there are things that you can do to  help. As tempting as it may be to ignore her back or try to make her jealous, it's not healthy or productive to do so. In addition, if your girlfriend is depressed or struggling with some other difficult personal problem, ignoring her back will only make things harder for her, and could really damage your relationship.  The “Elastic Band Theory” suggests that you can make someone want you by pulling away from them. It may work for some people in the short term, but it is not the type of behaviour that you can build a healthy relationship on.  One piece of positive advice that you can take from...

How would you rephrase that briefly using Vietnamese?
Cho cô ấy không gian. Tự hỏi xem có phải cô ấy thật sự muốn phớt lờ bạn. Cân nhắc khả năng bạn gái bị trầm cảm. Tránh trả thù bằng cách phớt lờ ngược lại. Chăm sóc bản thân.