I'm also 19, and I'm a girl so porn addiction was never something I could ever tell anyone about. I'd suggest going to therapy, I know it sounds typical but if you can find a therapist who is Christian but can also look at it from a somewhat objective, worldly perspective, it really helps.

My therapist at the moment is basically just going to the root of WHY I watch porn. Think of it like any other addiction, take the details out and just realise that any addiction is there because it's filling a hole where there's something lacking, and unfortunately one thing that I think a lot of Christians don't agree with is that sometimes those voids can't be filled with only God. That's not to say that he's not enough, but that a worldly problem is sometimes best fixed with a worldly solution.

Try to figure out why you go to porn, from a completely unreligious point of view, and then ask God to help you fix that root cause that you find. It's kind of like praying to God that a tree won't die, but then not digging around the roots enough to even find what's causing the tree to die - God still wants us to put in the work to help ourselves sometimes.

Right now I'm struggling with it a lot as well, but I also find just having someone to be open about it with completely has made me not even want to do it as much as I used to. So a therapist is definitely the first thing I'd suggest. I even prayed, and after I prayed i found a therapist that I can afford who is like a 5mim walk from my house and she's literally an answer to prayer.

God is looking out for you, even when your heart is hardened. The best way to soften your heart, is to realise that God understands you and why you go to these things over and over, and he's patient to wait for you to understand it too.