Accountability buddies

Hi
As someone who has already done what you're attempting (went from ~270 to 172 as of this morning), I think a buddy system might not be ideal. This comes purely from my point of view and my experience - so please don't misunderstand when I say this.
The way I see it, if you can't stick to something (any sort of commitment, not just health-wise), you have one of 2 problems. Either your approach is not ideal, or you're not actually 100% committed. If you find it really hard to stick to your routine/nutrition (btw - what are you doing exactly?), you should reflect and evaluate "Am I really in this for the long run, or is it just a feeling I have right now?" and if you can honestly, truly say that "yes" you are committed, then "What exactly am I doing? Am I maybe eating too little? Am I eating the wrong foods? Are my macros in check?" --> and my point being a buddy can't tell you what your own goals and motivations are.

Figuring things like that out is what enables you to stick to it for the long haul. That being said, I can also tell you right now: You will experience failures, you will experience setbacks, and you will question yourself at every corner. The trick is to not let that derail your whole endeavor, but to get back to it and realize that a temporary setback or failure is just that - temporary.

Sorry for the rant, but I've always felt that this specific goal is something that you have to do for yourself. You are VERY free to disagree with me though