I've had several occasions of my partner telling me that I have been being "mean" to him and he wants me to stop it because, he said, it's annoying. These certain "mean" moments are caused by sudden outbursts of my anger but like, in a toned down way. When I get angry I choose not to talk to anyone anymore because I can't control myself when I'm really angry and I don't want to hurt anyone with my words that go on for hours, then days and even to weeks (whenever I feel like my anger has subsided, I then get extremely guilty or feel really bad to people I lashed on to and then I'll get very distant from them after apologizing many times).

Last night, my partner and I were in a call and were happy talking about random stuff but I suddenly got mad out of the blue and got the mood ruined. I can't remember if it was actually random anger or my brain just deleted this certain part when I got mad so now I can't remember anything about it. Earlier today, he told me that after being "mean" last night, I am now acting like a different person because I was being nice and is acting like nothing happened last night. I already expressed my apology to him but I really feel like it isn't enough and I want to help myself get out of this shithole of a mind. Do you guys have any advice how to control your anger whenever this happens?

(Additional)  I also feel like this is really toxic for him and I don't wanna make him feel like shit because of stuff I do that I can't control (or I feel like I can but I don't know how to). We're just new and got into the relationship just a few months ago, but I feel like it's better if he finds someone else who isn't unstable and actually knows how to manage herself, BUT I also don't wanna be left again and it will hurt really bad if he leaves me now or I leave now. I am really confused. I hope someone gets to leave advice about this one. Thanks in advance.