The girl you like is always chatting or texting online, chatting with people you know or don't know. What would you do?

I think the most important communication between two people is. Regarding the questions you mentioned: First, it may be that you don't care about her so much that she will chat with others when she is bored.

Second, it may be because you are chatting with another MM, and she found out that she was very angry, so she chose this way to annoy you [note: if you are a playboy].

Third, maybe she just likes chatting with strangers (poor self-protection awareness)

Usually, you should pay more attention to her. For the question you mentioned, you can ask her why. Remember: be sure to ask with concern and never lose your temper with her. If you lose your temper, she will not tell you why.