What is the meaning of vaentines day by Linkin Park?

Answer 1

It means that his girlfriend left him and he's never spent a Valentine's Day by himself or in other words been without a girlfriend on V-day

That's a good answer and all, but, acctually, Chesters father died on valentines day, or one of his family members, im sure it was his dad though, hence a line from the song "And the ground below grew colder As they put you down inside"

Answer 2

Linkin Park tends to leave their songs open for interpretation. They make it a policy to not tell fans what the songs mean. In my opinion, it's about losing love and finally realizing how much the other person meant to you when you realize how lonely you feel without them.