None of the sentences are correct. Here are the corrections: 1. We've been friends for many years. (This means you are both still friends). 2. We were friends for many years. (You are not friends anymore). 3. We are friends. We've known each other for many years.

Oh gosh .. thank you Angie. I didn't notice that word during I wrote

Also when you ask this question, the word "which" should be used. The spelling you used refers to something you would see on halloween.

We have been friends for many years.