Feeling indescribable guilt and horror because of something I did

So I’m a 35 year old male with quite severe OCD, depression and anxiety. I’m usually a peace-loving guy and I hate any sort of violence, be it verbal or physical

That being said, I do have anger issues where I tend to be quite brutal towards the people I usually love and I feel awful later on, so you can only imagine the guilt that lingers on after I’ve said something hurtful.

The thing that is absolutely torturing me now is what I did two years ago when my mom and I had a heated argument. Basically, she was sitting down and I was standing next to her, not facing her direcy, when she said something that triggered me so much that I raised my hand as if to hit her. I don’t know why I did it or how it happened, but I’m absolutely sure I’d never do it, no matter what. It was only an impulsive gesture that happened out of nowhere and there are no words to describe how awful I feel.

Fast forward to today, when I’m talking to one of the most amazing girls out there. Everything was going just fine until I remembered what I did and now I feel unbelievable guilt and shame that makes me think I don’t deserve any kind of love or affection from anybody.

Please help me out here because I feel beyond horrible and I don’t know what to do. Should I eventually confess to the girl and just say what I did? I feel as if I’d be a liar if I kept it to myself but I’m also terrified that she’d leave. I’m honestly at the end of my rope.