Who is right in my friend group?

My friend J has been having exams, finals, living all on her own at 22 so working like crazy to pay for her mortgage, university, car and other expenses. I saw her on the verge of burnout so I asked her if she's ok and she burst out crying, saying once her school year is over she will finally sleep. She's basically sleeping 3 hours a night in order to keep up with the exams and bills. I offered to help her study and whatever else she needed.

We had a friend lunch and our friend S (22) texted that she hopes J at least did her hair this time. No one responded.

We get to the restaurant and 20 minutes later J shows up without any make-up, bun up, dark under eye circles and some dress pants and a pretty blouse. S said to her "Wow! You look like 💩, couldn't you have a least put on some make-up for our group pictures." J apologized she had rushed here and was very tired. Then S said "Oh please, you don't know what tired is until you're a mom. Come at me with that once you have 3 kids like me." This is her go-to response anytime we say we are busy or tired, but before I said anything J snapped. She said S has a husband who gets paid enough for her to send the kids to daycare everyday for 6 hours, her mom also lives with them and as she had previously bragged about, her mom helps with cooking, cleaning and night shifts with the kids because S is always "exhausted." She said S has no drive other than being a wife who shames and judges other's struggles as if she had any clue about being in the real world, that she would not survive if her husband decided to leave her because she's never worked.

Some friends are saying J was too cruel about coming down so hard on S, that she didn't mean no wrong and we all know how she is. S is crying and hurt saying J is simply jealous of her.

I disagree, I feel very proud of J and how much she's working for her dreams, she's so sweet and only minds her own business. What do you guys think? @Avery I'm not gonna continue being friends with S, she's always shown her true colors and I'm done making excuses for her.