Which friend is in the wrong ?

Okay so this might be a bit lengthy. I’ve had a trio friend group for a few years now .. both of them are close with me but I actually met D through S .. nonetheless we’ve always been really great friends. We’ve had our group chats, hangout sessions, 3-way calls etc. since forever. Well D & S live very different lifestyles. S is engaged & has been trying with her partner after a loss this year she’s in a committed healthy relationship & basically they’ve just been trying for a child without it really happening. D on the other hand is single like myself but she’s more into hookups & casual things. Nobody has ever judged her for that we always just told her be careful. Well D found out a few days ago she was pregnant called S crying & said she was going to be getting an abortion because it’s 3 potential fathers & no way to know without testing it was all in the same week. From what I was told at first S was extremely supportive like I was basically just telling her we would be there either way but the day after D found out she was pregnant & left the doctors office to confirm it she called S again crying saying she didn’t know what to do & telling her what all of the potential dads said .. I guess S decided this was all too much for her & has said she doesn’t want to be involved with D right now & would appreciate to be left out of it. D feels like this makes her a bad friend & says whether she keeps it or not she doesn’t think they will remain friends. S is also not really wanting to get back in contact with her. I sympathize with D because I know it’s a hard position to be in but yet I know her so I know she’s always been irresponsible & her excuse here was simply “she didn’t think she could get pregnant” .. but I also sympathize with S because all she wants is to be a mom & she didn’t come outright being spiteful she just said it got to be too much. When S told D she was just feeling a bit sad about it not happening for her but everyone else D instantly jumped to the response “At least you know you can get pregnant it’s just not time & it could be your partner” which is brutal to say when someone is already really sad about their loss & their struggle. I’m on the fence & directly in the middle of this. Thoughts?