What the hell?

My good friend told me she is pregnant. Not that I wasn't expecting it cause they use the pull out method and no other birth control. But she told me she wanted a baby so bad a while back and he did not. Well she told me he would pull out and cum on her boobs. While he wasn't looking she would grab the sperm and insert it into herself. Now this is crazy and THIS IS HOW SHE GOT PREGNANT. I want to tell her boyfriend but what are the odds he's going to believe me.... Ugh. Just wanted to share how disgusted I am
Edit: she's NOT MY FRIEND anymore. This is absolutly wrong. I cannot be friends with someone who did this. And all you saying I should not tell cause she is my "friend".... Is messed up. 
I did decide to not tell him but just to leave that so called friendship.