I need some tips on how to quit please

I have been addicted for a few years now and I don't know what to do on how to cut off both masturbating and porn.

Normally I experience anhedonia and just plain old boredom and it's a part of an mental disorder I have so when I feel bored I feel triggered.

I will either burn myself, masturbate and watch porn or sit on my phone for an unhealthy amount of time until this boredom feels lessened.

Friends have shown me porn and I got used when I was a lot younger so I guessed that messed me up a bit. I have a long history of sexual trauma.

This addiction is affecting me badly, I feel like hurting myself more every time after I masturbate. I struggle to think clearly and have little motivation.

Ive went without it for 9 days and I could think so clearly and felt much better...and 15 days was my best

but now I've relapsed multiple times and feel sick.

I just want to quit. I can't have a therapist or counselor. This is my first time talking about this ever because I feel so ashamed of myself

I need tips on how to quit both wituout links please I need your help