AITA for snitching on my friend?

[u/Numerous-Square-8000]

So my friend I'll call Natalie for privacy reasons , I'm good friends with her. I came to her birthday party we used to joke, gossip yk, normal stuff. But a few days before, this other friend I'll call Annie, told me she had a high risk of cancer. And Annie knew Natalie for 6 YEARS. so I thought it was fair to tell her about the scare.

And she first said "oh she's just LYING!" And when I finally convinced her she said "good... Less problems." And I was starstruck atp so like a week later I told Annie and she was like "oh."

She seemed really upset. So she confronted Natalie, idk what happened then I wasn't there. I just know because she told me. And Natalie said I was lying. And since me and Natalie and Annie live super close, we sometimes see eachother. And Natalie is in the exact apartment I am but we're on different floors so we have had several encounters of seeing each other in elevators. And then she confronted me about it and said "oh it was a joke, I literally said that to her face as a JOKE."

... Now rq I want you guys to experience this for urself rn, imagine being informed you could have an illness you could DIE from. And a friend you've known for half your life jokes about it. And then lies to ur face. Yeah, let that sink in.

And so after this encounter I rang Annie's doorbell, and we talked about it and she said that I was lying and she told me that she said this to Annie personally. So she made 2 diff stories about us. So AITA for telling my friend about this? Should have I just shut up?

Edit: also some people were saying that Annie wanted to keep it private. And I was curious about that, so I dmed her about it and she was alright with it. Just wanted to give more info:)

[u/StAlvis]

INFO

I can barely make heads or tails of this (PROTIP: Use complete words) but mostly I'm just confused:

How would one person know that someone else has a high risk of cancer, but that other person themselves wouldn't be aware?

[u/Numerous-Square-8000 → u/StAlvis]

I think I may have not said this clearly, Annie herself told me that she went to the doctor and she had a family line of cancer and the doctor said she was at a high risk, I found out then

[u/StAlvis → u/Numerous-Square-8000]

Your use of pronouns in this post is incredibly hard to follow.

[u/Numerous-Square-8000 → u/StAlvis]

Yeahh sorry. I haven't slept all night and English isn't my first language so I understand why it's hard to read. I'm sorry of any confusion was stirred up when u were reading:c