Why did my (24M) ex (21F) put me through all this?

Ive accepted that I don't want and wont get closure. But I don't understand her reason for everything.

A month before we broke up the second time, we broke up for the first time. She cited that we were incompatible, she didn't feel a spark, and our conversations didn't flow. Then a day later she said she was really sorry and that she attributed the breakup to her always hating herself. She also promised that we would work through our problems and that I shouldn't be afraid of her leaving again.

Anyways, the second time we broke up it came out of nowhere. The days before that nothing seemed out of the ordinary, she actually considered staying over at my families house with me. Then when I saw her she was in a sad mood, and said that she was in a better place and that we are incompatible, that she doesn't like attachment and isn't ready for a relationship.

The other issue is that she was the one who lead me on to believe that we were aligned. She said I loved you first. She told me that I gave her butterflies early on. She said I made her feel safe. She let me stay over at her families home. And the weeks after our first breakup she kept apologizing for what she did.

Then after we broke up she sent me some breadcrumbs which I ignored.

OH, and she was on bumble days after we split.

None of the situation makes any sense and I'm slowly getting over her but it's still something that deeply frustrates me.

I miss her a lot, but as my friend told me, she's a walking red flag that I was too infatuated with to see.

Tl;dr My ex led me onto believe that she wanted a long term relationship, just to suddenly dump me twice. First time blaming her mental health, and then the second time citing she was in a better place.