Hi Chassidishe buchur, I'm also a Chabad chossid, married with two kids, 30 years old, BT. I'm sure you've heard this so many times, but your struggle is so common. I see a lot of my own issues in what you've been say. For instance, I'm naturally a depressive. It's easy for people like us to get down on ourselves. But for sure 100% the main thing is that you need to be b'simcha not just about your victories (however small they may be, for instance, how amazing is it that you're only mz"l 4 out of 7 days?!?!) but also be b'simcha for the fact that Hashem gave you this taava and addiction. In a big sense, it's not you're fault, Hashem made you that way in the same way that Hashem makes people with mental disorders and physical/mental disabilities. How silly would it be for them or anyone else to blame them when Hashem decreed that that should be their chelek in this world?
But even so, this addiction is such a blessing that I haven't even fully been able to understand how great it is. We see it only on the receiving end:
we are the ones who have to fight the daily struggle,
we are the ones who have to deal with the guilt and shame that follows,
we are the ones that have to feel like we're leading a double life. But from Hashem point of view, this taava and addiction is a huge way for us to come closer to Hashem. Not everyone gets to know what their shluchis is; how amazing is it that Hashem has literally shown you yours?! By engaging in this holy avodah, you are able to come close to Hashem in ways that most people are unable to. Honestly brother, I feel like the Alter Rebbe was talking to people like you and me, flawed people with big yetzer hara's that want nothing more than to catch us with our pants down and say "told you so!" even though he's the very one who made us unzip in the first place!! The Alter Rebbe/our Rebbe knows all our issues, we need to believe that the Rebbe knows our strengths and believes in us more than we even know/believe in ourselves.
Some practical guidance though, I would definitely explore
ALL of the resources that the GYE website has to offer. Ask yourself if you've read all of the articles, tried all the tools, listened to shiurim, developed a solid list of contacts for when you're itching for the next fix. I can tell you right off the bat that according to the attitude principle #1 of the GYE program, shmiras habris is not just "another thing" that people may be lax in like not davening with a minyan or missing krias shima (neither of which are ok although ppl do it, similar to all of the people who talk during kaddish in 770 mit a chutzpah) shmiras habris is literally the yesod foundation of our avodah! We don't talk enough about it in chabad literature, but it's the truth. Working on our shmiras habris is so important, probably more important than any other thing in our avodah. Feel free to reach out to me if you need chizuk:
iwtbf613@gmail.com. I'm here for you!!!