I have anger issues and haven't been able to reach out for help because I'm ashamed to talk about it

TW: abuse, self-harm, suicidal ideation

So I have anger issues, which is a somewhat recent realization for me. I've probably had these problems for a long time but I just wasn't self aware of them. I don't wanna talk about them because I don't like talking about bad things I've done/thought/said, because I don't like people getting mad at me. When people are mad at me, I get REALLY mad back.

A lot of these issues started once I realized how much my life sucks and how unfair some things are. I have anger towards a lot of things in my life right now. My family pisses me off because we argue a lot, I hate politics right now, and I'm questioning my gender and going through a lot of dysphoria. My family is especially triggering for me because we yell at each other quite often, and my parents are transphobic, so I'm always on edge around them. They are also just pretty annoying people sometimes, and I'm quite irritable. I don't get physical often but I have been physical when I get REALLY angry. My parents have been physical with me in the past, too, but not that frequently. Mostly it's just yelling on both sides. If I'm not being mad at someone else, I might self harm or ruminate, usually on all the things wrong with life but sometimes on suicide. I punched myself in the stomach a minute ago because I was so angry. Sometimes when I'm REALLY mad, I feel like a different person. I can't even talk myself out of lashing out when I get to a certain point.

I was making a post about my anger issues on another subreddit, but I deleted it because I didn't want people getting mad at me in the comments and trying to fight me. I feel embarrassed about what I've done but also don't really wanna be mad and mean all the time anymore. But it's so hard to control and I just don't know what to do.

I don't really want to get a therapist because I've tried to get one in the past, but was never able to find one that suited my needs, and the whole experience has left a bad taste in my mouth. Plus I'm not great with talking about stuff (I prefer writing, I already journal). I'm considering doing boxing or some other exercise. But what else should I do? Idk much about treating anger issues. I know how to treat depression and anxiety, but not overflowing anger. Give me advice, please!