I once dated my first cousin for 9 months so me and my friends would have something to talk about
Why did you and your friends need to talk about that?
It made for an interesting joke when we talked about it daily.
Being with friends and talking about cool things is what everyone likes to do, but this was rather different. Incest is taboo, wrong and must never be done. Thinking upon this I hope you never try it again, it can mess up the minds of those involved and make them find other incestuous things fun as well.
My friends don't feel bad about me dating my cousin. I don't think it was a wrong thing to do.
You shouldn't try to impress your friends at the expense of someone else. Plus you and your cousin should both know that dating each other is wrong and it's bad to have relations like that. It is good to hang out with friends and joke around, but you should probably find something else to talk about.