Hi,
commas are used on many occasions. For example, I would have used two in your sentence:
I know we use it before names when we talk to someone, for instance, but that can't be the only use can it?
I'm afraid I am not able to help you much, because I never had problems with commas, since they are used the same way in my native language. Generally speaking, you should use commas whenever you feel the reader should make a little pause. Listening English will help you understand the rhythm, and practicing reading will help you recognize the most used patterns for punctuation.
