Denial and minimization are ways the brain reduces pain. It's not "just" denial - but it's a coping tool of sorts, one that helps most survivors get through it. The problem is when the denial or minimization is no longer serving us well and become maladaptive coping tools... like you are experiencing now. As you know, the truth and the pain with it has to be dealt with in order to heal.
Denying or minimizing can also come from internalizing the abusers messages that it wasn't really harmful or wasn't really trauma or etc. That's what they wanted you to believe, and kids natrally soak up such messages from abusers.
Acceptance of trauma happening is hella painful. As the wall of denial comes down, it's going to feel really painful - and that's ok. Just as long as you don't start drowning in the pain.
If you find yourself able to face it at times, and other times you struggle with denying it... I'd suggest taking the pressure off to face it and instead find ways to build up other coping tools. Like self care and lowering overall levels of stress. Then when you have more space, the walls of denial will be easier to climb over.
It could also help to take very small parts of it to work with. Like self directed exposure therapy.
It might also help to look at core beliefs about it and fears about what it means "if" it is true. For me, I couldn't acknowledge trauma was real until I challenged my belief that the trauma made me a horrible person.
What you are struggling with is super common. It has taken me a lot of time to be able to say or write to myself certain traumatic events happened to me.
It will get easier over time to climb over the wall of denial.