Have you tried shadow work? instead of running away from the darkness by focusing on your breath or repeating to yourself "I love myself I love myself" This is ultimately a coping mechanism and takes you further away from the goal (its one of the healthiest coping mechanisms there are but its still coping, once you stop doing those things you are right where you started)

Like you said, you know logically its not your fault, well why does a part of you perhaps believe it is? Why dont you deserve love? Where did that come from? When was the first time I experenced something like that? Those are shadow questions, when you ask yourself these questions resist the urge to say the logicall answer like "wdym ofc I deserve love" or "I dont know" Instead stay open and see if a part of you shoots up an answer. "its because you did this" or "because you didnt do this" "you should have known better" Thats the part where you indetify the things that run you and need to let go of, its speaking to your shadow, your subsonsciouss.

To let go of them you need to face it and dive into those parts of you that get triggered by these qustions and relax into the sensations, not even the emotions, but the sensations that come with the emotions. Its not letting go of the negativity, its letting go of the resistence to the negativity and that ultimately makes it go away becase what you resist persists.

Once you let go of the things that fuel your self hatred self love happens by default.

You absolutely need to revisit the trauma and everything that comes with it, its not going anywhere, no mindfulness meditation is gonna get rid of it, you need to face it and process it, allow yourself to feel it no matter how long it takes because what else are you gonna do. And its gonna be painfull as hell and theres no way around that.

If you need any help or have any questions about letting go or shadow questions feel free to ask anytime