I need advice, former relationship, now friends

I had a long distance relationship awhile back with someone I thought was perfect for me. We read books together on the phone, talked about our common interests like political philosophy, philosophy, other nerdy stuff, pretty much everything, all our kinks and our feelings & our entire history's. We could talk about anything, and became best friends before being in a relationship.

We ended up in a disagreement about him not calling much & ignoring my messages, conversation didn't seem as deep. Because it was long distance, it was difficult, because the whole relationship relies on talking to connect and we were talking less & less.

Anyway, I got upset at some point and instead of talking to me, he distanced himself and never called me again, even after saying he would, and even a specific day we were supposed to talk, he actually lied to avoid it and then told on himself by accident because he thought I noticed the contradiction! (I was busy & didn't respond right away,) And we were so honest before, so at that point I was done, and just so mad that we were going to try to work through things like that, and he just totally shut down and shut me out. Honestly, I think it's his mental health, he gets adhedonic. He has avoidant attachment style, as do I, so, it seemed predictable that this could happen, but we had planned for it :/

They are also super conflict avoidant, they knew I was angry because I said "I am mad" "I am upset" etc. I didn't personally insult him or accuse him of anything, I just said I was angry at how thjngs were going and not to have any access at all to talk to my partner. I know they have an abusive parent, so I was very careful not to be too intense or mean at all, but he's sensitive and terrified of people being mad at him.

So I think that's why he ultimately just apologized, said he was stressed, and sad things were going that way, but distanced himself.

We never did discuss what happened, really, in any detail. We just broke up and I stopped responding because, clearly we needed some space.

Ultimately, I did want to be friends, because they're important to me, they were my best friend for awhile & we have a lot in common.

I told him I wasn't mad anymore over a month or so later.

After a few weeks, he started talking to me again every day.

At the time, he did bring up the relationship, and I said I wasn't ready to have that conversation or say anything about it.

He doesn't call, we just chat through text, sometimes a decent amount. We do not really talk about the relationship, we never have talked about the end.

I once brought up that I'm sad about it sometimes, but said it was for the best.

He said "I don't even feel like myself anymore but sometimes I miss it too."

Although I want to be friends, and I don't really want to get back together, mostly because I know the sane thing will happen & long distance is too hard, and I'm honestly thriving single right now... I do feel somewhat painful feelings sometimes- like, I really loved this person & wanted to experience so much with them & read many books together, for years. But, I can't deal with someone who cannot maintain the most basic emotional connection, he just isn't in the space to be in a relationship, tbh. He has more personal work to do, imo.

And long distance is rough, I just don't want to do that anymore.

But I feel so jealous that he'll flirt with other people, and, for me that's extremely odd, I am never jealous, I'm polyam by nature & we were polyam at first (he decided he didn't want that due to his jealousy,) i literally helped him set up a dating profile & helped him talk to other ladies 🙃 but now, it just feels different, like he just didn't like me anymore & like our relationship is tainted by dishonesty. But I don't know how to navigate that, and I'm not trying to get him back so obviously he will & can move on...

I can too, but I'm not interested in anyone or meeting anyone.

I just want to know, if we should actually talk about things, and if not, should I even be in this friendship or is this toxic? I am a bit nervous this is toxic because of my past & because it just feels disrespectful of him never to be willing to discuss it.

Is this ok? What should I do?

I'm capable of managing my feelings, but, is something off about this? I've never ever had a breakup where we didn't talk about why it happened- but also I have a good idea about why it happened so am I being petty??

I haven't even been ready to talk about it & it doesn't sound fun, but it feels like something is just hanging over the friendship now.

Eh, thoughts?