Unhealthy Dynamic - Need Advice

I 33F have been with my partner 32M for about a year and a half. We had been together for about a year before and we broken up for several years (and both did many years of therapy), and then got back together. The communication seems much more open this time around. However, that’s revealed to me that he has a lot of trauma I was unaware of before.

Every so often when he feels like we’re getting closer or like he’s somehow being pressured into something more by the situation/society (before a vacation, Valentine’s Day, etc), he starts to spiral that things aren’t going to work out and he doesn’t know how to get past them. The first time it happened, he said we should break up. I didn’t fight him and said okay. We share a lot of the same friends, so we were still around each other and he acted very much the same, and after a week he said he brought up breaking up so that we could talk about it, not because the choice was set in stone. I explained that he sounded like his mind was made up, so I wasn’t going to beg him to stay. We did talk, and we stayed together because the spiral was caused by his trauma and the feelings of pressure (not caused by me, he said I am not the source of that at all), and not anything actually wrong between us.

It has happened again twice since then, and although now he brings it up as a conversation rather than a finality (and definitely not as a threat or anything), it feels like I have to therapy him out of breaking up with me every 6 months or so (I just listen and ask questions - I don’t actually try to talk him out of it). I don’t feel like that’s healthy even though I know that it’s a trauma response on his end. This should really be something he works through with his therapist, but I also don’t know because I don’t want to shut him down when he’s telling me how he feels and communicating openly and vulnerably with me.

He also recently said he doesn’t fully trust me and explained he feels like he has to keep some distance between us in case I decide to leave. I don’t know what to do with that.

What do I do? Is there a conversation I should have? or should I just end things?

TLDR; my partner has a lot of trauma and kind of uses me as a sounding board to talk himself out of breaking up with me. How should I handle that?