i see this all the time with people i have lifted with in my day. Although not everyone has battled back from tough mental times as you have, they have lost their gym drive for a multitude of reasons: work, kids, life, laziness, lack of results, injuries, etc.
The programming should be secondary. As Consul said, your goals should be simple and achievable at first. Even if it is as straightforward as simply getting three days in the gym for four weeks. A common mistake i see with people returning is they come back like they never left, expecting to be able to perform the same lifts at the same weight for the same reps. Then when they do not perform to their own expectations, they get frustrated and program flip, or worse, stop lifting again.
531 is a great program for returning to strength training, as long as you program honestly. It is good because it gives you the opportunity to hit the major lifts in a way that you can always challenge yourself, and still feel successful by setting PR’s and consistently increasing weight from week one to week 52.
Figure out what you enjoy about lifting. What you want to accomplish by going to the gym. If you want to increase strength, program for that. If you want to get huge, program for that, but be realistic and set short-term goals that give you the best opportunity to achieve your long-term goals as well.
Based on your post, I would recommend simplifying your diet. Eat well, not more. Adjust your diet as your lifting becomes consistent again. Really simplify. Good meals, protein, and sleep. Keep your house in order and improve with addition by subtraction. Do not try and do too much too fast.
I would also recommend hitting the big three lifts with 531. I personally do not program military press with 531, but that does not mean you cant. If you hit the big three each lifting day, you will be in a much better place in 4, 8, and 12 weeks.
Stagger your deloads so you are not getting into singles during the same week. This may not make a difference early, but as you work through some cycles, it will make a big difference later on.
And most importantly, celebrate the small victories every day. Be proud of your new PR’s, even if you once were stronger. Gyms are filled with yesterdays stories of strength. None of that matters. All that should matter is what you do today. The weight on your back or in your hands right now. Leave no doubt.
This is one of the best posts ever on this forum. Thank you mate.