Feeling shame and needing support for how to manage emotional outbursts

I’m really struggling and feeling a lot of shame around these emotional outbursts I have with my fiancé. When we argue or disagree and it gets heated I just bubble up and either slam a door, or scream, or throw things, or hit an inanimate object. I notice that I get more heated when I feel like he’s not listening, or blaming me without seeing my side, or when I think he’s being defensive and stubborn, etc… I understand that there are some thoughts I have about him when we argue and also a lot of times it feels like the feeling rises in my body before the thought becomes clear. I get this feeling in my body that just feels explosive; like I need to run and scream and break some old junky furniture.

It feels terrible because I have all of these thought about myself because of it…that it’s a really bad way to handle emotion, that I’m a bad person because of it, that I’m going to ruin our relationship because of this, that it scares him and that makes me the bad guy, that maybe I’m being violent and abusive like my mom was when I was a kid, that maybe there really is something wrong with me like my mom tried to make me and everyone else believe when I was a kid, etc, etc… I grew up in a violent, abusive home so I know that this is most likely a patterning of my nervous system from childhood, but I feel really awful and wish I understood better how to down-regulate my emotions in the heat of the moment. It’s not all the time, in fact most of my adult life I haven’t even experienced these outbursts, but they’ve been coming up the last couple of months with my fiancé and it just feels terrible.

I’m working on getting in to see a therapist but have to wait a bit longer for my insurance to get set up, and go through the process of finding one that accepts my insurance, etc… How do I handle these emotions in a healthy way? Any insight and support would be great.

Thank you.