Most of the ex-sjws I have talked to have said leaving the movement was like the scales falling off their eyes - one incident made them think "wait, are you guys for real?"
It seems like a lot of them tend to leave when they start getting attacked by another faction. If you're a lesbian feminist who's under massive heat from a bunch of bearded trannies calling you a bigot for not being willing to play with their girldicks, you have to start looking at your rhetoric a little more closely and decide where your line actually is. Being open minded is a good thing, but legally enforcing "social justice" is just another type of horror show. You should be able free to be a hideous overweight genderless blob if you want, but then I should still be free to be an asshole about it.
Also, perhaps now that she is in more of a serious relationship, she is pondering having children...and that can lead to thoughts of, "Is what I believe what I want to pass on to the next generation?"
It's a lot harder to keep a hardcore progressive mentality when you throw children into the mix. Most of the real insanity comes from college campus, where everyone lives in a bubble made of nothing but adults. You can even kind of see where the mentality is coming from, as there's this withered little root of a good point under most of it. But when you have a child looking up at you expecting you to keep them safe from violent perverts and random terrorist explosions, it's a lot easier to see what the red team was worried about.