First, tell her why you hung up. Because she might be thinking you hung up because you were mad, and it would help to let her know that’s not why. Then, I’d just talk to her (maybe over text if that’s easier) about what happened and spend some time talking about how you can communicate when things are tense. I can’t have “fights” with my husband (who stutters) where we both just blow up and vent everything we’re upset about. He can’t do that. And that’s not a bad thing, because I’ve been in relationships where we had angry arguments where we were both just interrupting each other and raising our voices and kind of stream-of-consciousness letting out everything we were upset about, and that’s not actually very productive. With my husband, if there’s some kind of conflict that comes up, we try to just notice it’s happening, stop, give each other time to calm down, and then come back and talk about it, just kind of taking turns and letting the other person say what they want to say. And actually it’s a lot calmer and more productive and healthier than just being angry and reacting. So I’d try to set some ground rules together for how you can have arguments/conflicts in a way where you are both able to say what you want (even if you need to text some of what you want to say).