Is my ex a dismissive avoidant?

I'm torn on what attachment style my ex had. For context, we were together two years and broke up a month ago. The breakup was terrible. They sent me one big long text in the middle of the night and I haven't heard from them since. No conversation, nothing. I got the block on everything. They cited not having a lot of similar interests, along with feeling like they had to hide themselves and mask around me, along with feeling like I was violating their boundaries.

Here's where my issues lie. Said boundaries are hard for them to establish in the first place. When conflict would arise between us, they'd shut down completely, I mean go nonverbal. I definitely didn't help this, always poking and prodding and begging them to open up and tell me how to help but they just couldn't. But sometimes they would, sometimes it would all spill over in a big crashout. A few times they were so upset they just didn't text me for the entire day.

I am NOT free of blame in this breakup, believe me. I have unnecessary and inappropriate reactions to things that make me angry, I would make rude jokes at their expense, and for a long time I really didn't put enough effort into their interests. But when they did voice these concerns, I always did my best to make them right again and to change my ways because I knew I loved them and I wanted to be better.

And it's not like we never had deep, meaningful conversations about our relationship our the issues we had with each other, and when we did they were understanding and never turned into fights. We never cheated on each other (I think they didn't anyway) and there was never any abuse, though it is apparently relevant that they were pretty severely abused in their past.

It's also important to mention that, as far as I am aware, they are completely fine after all of this. I don't have any actual way of knowing otherwise, but they certainly haven't reached out or made any kind of indication that they're regretting their decision or even upset.

So what gives? Are they a dismissive avoidant? Or was I the problem the entire time and they were entirely justified in leaving the way they did?