You have friends here brother.
Many of us, myself included, have been through the same process and understand your situation.
I also used PMO and MO as a way of dealing with stress amongst other things, and that laid down the circuits in my brain to couple stress relief and MO. I do not know your situation, but the way I handle it now (on Day 62) is to change my surroundings, so for example if I am inside I go outside and look around, perhaps with a cup of some nice drink to sip. If I am in a situation where I cannot change my surroundings I say to myself that this is just part of the healing process and that I am rewiring my brain to not associated stress with MO, and that takes time and effort. But know one thing, the feeling will go away, it is only temporary.
I still get the urges in stressful situations but they are subsiding faster now since my brain knows I have no succumbed yet.
If you do relapse, don't take it as a total failure, it is only a speed hump on the highway leading to your eventual success.
Brother, we are all suffering like you, we know what you are going through, and rest assured you have our full and total understanding.
Cheers for now.