I have been skimming through this thread, it is rather large so i didn't catch every post but I can see that your ultimate goal is to put on some muscle without adding any fat and feeling healthy and strong once again.
I have been where you are at one point when I was trying to lean out for the first time in my life (naturally estrogenic and endomorphic). To make a long story short bro you are battling with your mind which keeps telling you to eat less and train more. If I were you I would do cardio in the am (empty stomach) 2x per week, 40 mins at about 150 bpm (heartrate). Then add in 3 20 min sessions after training. Don't train more than 5 days per week. If you are not "on" bro you are simply driving down test levels and jacking cortisol.....seriously which is a negative downward spiral.
When you overtrain, test drops, gains slow, depression sets in, cortisol increases, muscles flatten out, metabolism slow, lower back and ab fat increases, and overall you feel like a "fat-skinny" kid.
If you are a low carb person, just start out by eating carbs around training time, pre and post and keep protein intake through the roof. There is no need to feel hungry when dieting, grab some chicken, turkey or tuna and go to town.
Trust me bro, you need to get your metabolism and natty test levels elevated by training hard, eating solid, and RESTING. Hit the gym for 45 minutes hard and get the hell out. Make yourself crave walking into the weightroom, not dread it. Remember when you first started training and you could not wait to hit the weights, that is how you'll feel if you take some more rest days and forget about training. Just keep on the diet and come back ready to train.
I was at an all time low in body weight, test levels, emotional swings etc. i was lean but very "thin", like an underwear model type look. It took a while of gradually increasing calories and rest periods. Now, I year later I am 30 lbs heavier at the same bf% and same waste size etc. I train less (but just as hard), eat more, and am much happier.
Any way, I only read the first 4 pages of this thread but I can feel where your coming from bro. Just think how lucky you are to be lean and afraid to be fat than obese wishing you could be skinny.