Relapsed Last Night and Today

Last night when I went to bed I couldn't fall asleep so my mind started to wander. I started to think about porn and how good it would feel to masturbate. I tried to tell myself not to masturbate, but I couldn't resist my urge. After masturbating I felt horrible. I felt like a failure. I had another relapse today. This time I relapsed while watching porn. I really need to have more self control. I always tell myself that I'll never PMO again, but I always end up relapsing. I feel like this addiction will never end. It's ruining my life. It's changed me as a person. I don't think I'll ever be the person I used to be before I started PMOing. I'm depressed, I have severe social anxiety, and I'm socially awkward. All this was caused by my porn/masturbation addiction. I wish I would have never discovered porn/masturbation. Back when I discovered masturbation I never thought it would have such a negative affect on my life. Can somebody please give me some tips to avoid relapsing again. I really need some help.