Hey dhira,
I read your thread just now and as a fellow yogi/meditator I wanted to tell you you're doing a good thing by tackling this. I'm new here so I don't have a ton of experience or wisdom to offer, but I'm also striving for mastery of Self and realize how damaging this PMO habit has been toward achieving that goal. I dont know how consistent you are in your practice, but I'm certain that will be our source of strength through this dark period.
There was a time when I meditated twice daily without fail, but sadly PMO became the priority and the spiritual discipline fell to the wayside. A few months ago I attended a week long retreat at an ashram in SoCal. I was in the perfect environment for peace. No talking, beautiful grounds to relax in, and the support of a spiritual community, but i still snuck away at regular intervals to PMO in my room. Ugh, I can't believe I did that. I should have left the smartphone at home. Shameful.
Anyway, one of the first changes I'm making as part of my recovery is to become regular in my spiritual practice again. I know you have the strength in you to beat this. Weak willed people are rarely drawn to the yogic path, and it sounds like that is a major part of your life, so i know there's a fire burning in you to beat this.