I need advice, please! (Also, a lot of ranting)

Okay, so.

My two best friends are fighting and I feel like I'm caught in the middle. I’m not gonna use their real names so I’ll use their first initials: K and M.

So K found out her uncle has cancer a while ago and M didn’t show any concern because she had her own things to worry about: her grandma also has cancer and hasn’t been doing well lately. She told K that she wasn't sympathetic.

K got pissed off and hates M now.

K is trying to get me to fight with M now but I don’t want to because it’s between M and K, not me.

K gets so mad whenever me or one of our other friends talks to M. She even screamed at our other friend (let’s call her B) because she gave M a Christmas present.

Now, at this point, B and I think it’s completely ridiculous. First of all, B is the nicest person on the planet: you don’t yell at her.

Everytime I talk to M, K freaks out and yells at me and I have to make up excuses to why I talk to her. I shouldn’t have to hide a friendship I’ve had since sixth grade.

I feel like the rest of us shouldn’t have to deal with K’s attitude.

M even tried to apologize but nooo nothings good enough for K.

For one thing, K loves drama. She has also disliked M because I hung out with her a lot last year and K was really jealous.

Do you thing that K is being selfish and unfair or does she have a right to be mad? (this has been going of for two months.) Do you think she should let it go or move on?

How do I tell K that she has no right to make me pick a side.

(M hasn’t done anything since the first thing, K likes to be dramatic and start pointless fights for no reason.)

I really don’t wanna lose either of them because neither of them had ever done anything mean to me or gotten in a fight with me. I just wanna know how to get K to forget it and stop being mean to M.

M was just having a bad day. She didn’t mean to make K upset. Now M is really hurt because K is trying to get everyone to hate her.

Please, give me any advice you can. Thanks!