Can I ask what your own 72 hour rule is? If that's not too personal
I used to feel like a "functional alcoholic" because I would drink and it would help my pain. I would drink a little all day just to keep my anxiety down and be able to function. But as my desire to CTB increases and so does my depression the alcohol teeters a line between making me feel better and sending me off a cliff (literally)
Not too personal at all! Although I do appreciate the courteousness :)
Basically, when I've decided "yup, no doubt about it, I'm ready to leave this earth. I'm gonna do it, I'm going to kill myself", I have to make myself wait at least 72 hours before I actually make it happen. I won't say my exact age, but I've lived long enough on this earth; what's another three days? Maybe I can go on a little road trip, see some places I'lll never be able to visit once I'm on the other side. In that time period, I'm allowed to do anything pretty much, importantly I'm also allowed to prep for my suicide (my method is a little involved and takes time to prepare and set up) and write notes if I feel like it. If
at any time in that period I think, even for a split second, "Well, I dunno, maybe living ain't
that bad..."
*BAM* my timer resets. I have to wait another 72 hours before I'm allowed to really do it.
Many of us (including myself at times) would beg to differ, but we have to admit that suicide is often something done impulsively, or at the very least something we have to push ourselves hard to do in the moment; we still have our survival instincts, after all. Forcing myself time between the decision and my actual death gives me time to simmer down, even if it takes me 60 hours to realize "ugh, okay, I guess [insert immediate circumstance here] actually
can be dealt with

". It doesn't allow me to jump the gun. And it's saved my life multiple times. I've come real close to those 72 hours, but my "timer" has never struck zero since I implemented the rule at the start of my 20s.
It's hard sometimes. I had a particularly hellacious Sunday, I was in my living room screaming at 5:00 in the morning, eyeing my camp stoves and thinking about the gun under my bed, thinking "fuck those 72 hours, let's just do it now, come on Bikishii you pussy just fucking do it" but even in my brief moment of insanity I kept that rule in mind. If I hadn't done that, I probably wouldn't be here to tell you about the 72 hour rule right now. So I think it' worth it.
Just something to bear in mind if you've decided you're really gonna do it. You've made it this far. I know sometimes we keep going and keep going until we just can't take it anymore, but just keep going for another three days once you've committed to the decision. See how you feel. Be honest with yourself and reset the timer if you have even the slightest inkling of hope. I can't promise if you'll feel better or worse later, but you'll at least have some time to get some clarity. It's worth a shot.
