Need help communicating.

My partner and I both have trauma in past relationships, PTSD and BPD diagnosis for both of us. I've been in therapy for 8+ years now successfully. I've been doing better overall but recent twists of fate have me needing help.

We had an online friendship for 5 years, and ended up together after I divorced my ex spouse. Theyve been living with me several months now. We spend a lot of time together and there seems to be periods where all were doing is disagreeing and arguing. Living tense. They tend to lose control in situations and assume the worst of me or like catastrophize. I find It rlly hard to communicate in healthy ways and it's breaking both our hearts bc we care so deeply but we seem to be like on eggshells or already agitated before a big argument sets off. A lot of the time idek what it's about it just goes downhill so fast.

So I'm looking for help in curbing the negative communication and connect in easier ways.

Thanks. I'm like tore up about it. Idek how to unpack it all.