I have seen way too many posts recently using "your" in a non-possessive manner and it is starting to frustrate me. It is not just here though, I still see it in the work of people twice my age. I'm not saying I'm an English major or anything but I'll try to explain it as simple as possible.

If you are accusing someone of something you will most likely say something like "you're a lying son of a ......"
You use "you're" because it is a contraction of the words "you" and "are."

If you want to use the word "your" in a possessive form, then that makes sense. For example, If you were telling someone their hair looked nice you would say "Your hair looks nice today." You use "your" because it is their hair.

I'm not trying to sound like a conceded jerk for posting this, just trying to help people with a very common problem.

Hoped this helped :D