AITAH for (apparently) breaking up a relationship?

Okay, so I'm in a friendgroup of 4. Sasha (f), Julia (f), Sam (m) and me (f). Julia and Sam have dated for over 2 months now. Sasha, Julia and I have always met up sometimes without Sam so we could have some girltalk. Sam was fine with this.

We met again last week and Julia said she wanted to break up with Sam and she had been thinking about this for a month. If it would have been a new thought I wouldn't have said anything but since it'd been a month I told her that if that's what she wanted I supported her and if she thought it was right she should do it. I didn't say anything negative about Sam, I just told her to do what she thought was right.

She did break up with him, and for some reason she told him she'd talked to Sasha and me. When we saw Sam the next time he got mad at me. Not at Sasha. When I asked him why just me he said him and Sasha had talked already and she had told him I had encouraged Julia to break up with him. Sasha found an excuse to leave, so I had to sit there alone and listen to Sam being completely pissed about me 'causing his break up'.

I got away from the conversation but he's been texting me about it. Sasha is texting me with an apology for telling Sam it's my fault but I haven't responded. Julia hasn't been online. I don't think I'm wrong here but Sam yelling at me this bad and spamming my phone like this has got me to doubt it. So, AITAH?