Yeah I found the same. After I did the exercise grind for a bit of time I suddenly found out that my cravings for usual unhealthy foods have been reduced.
My trainer and doctor say that we have various receptors in our bodies tuned for our current way of life and that diet and exercise re-program these receptors which, yeah, is what I observed as well.
RE: your lack of motivation for working out, I found it is related to the type of exercise. The start of my journey was a series of train wrecks. I constantly stumbled on 22-year old boys whose wisdom was "get on the bench press, bro!" which didn't work for me. It was almost harmful even.
After going to physiotherapy for a while I then started training under the tutelage of the same people and I am already better. They are very careful not to over-strain me, give me just enough cardio to keep my heart pumping but not to make me wanna die, exercises are carefully tuned to strain me a bit but never too much. They don't give me big pauses between exercises (60 - 90 seconds) however. Some exercises are mostly stretching and "activating" a certain muscle (meaning just exercising it a little without any strain).
Not sure I can translate that to a workout strategy for you but these items might help:
- Do 3 series of each exercise. If it's too much then 2;
- Do more reps per series;
- Rest until your heart calms down slightly but not beyond that;
- Introduce a hard cap on the workout session -- mine is 1 hour. This was a huge struggle because I wanted to do all the exercises but there's no way to fit all in 1 hour (did that mistake several times);
- Start with slight cardio -- 5 or 10 minutes. Don't make it the focus of the session, it's just to start you off (a mistake I made many times);
- The moment you start feeling a tormenting strain is the moment where you train for 2-3 more minutes and cut the session short;
- If that moment doesn't come, still stop at your time cap.
The main point is to feel energetic and rejuvenated after the workout. Not "OMFG I wanna die!". My trainer / physiotherapist / masseur told me this is an extremely common problem for men because a lot of them just hang out in the gym and their main motivation is show-off and competition with others. He says there's a million ways to make yourself feel better by exercising and honestly? I believe him because it is happening to me.
Finally, it's the most normal thing in the world to fine-tune the exercise session to your specifics and you shouldn't try and imitate other workout regimes if they don't work well for you. My trainer quickly found out I have strong arms, shoulders and upper back and is rarely giving me exercises for them -- just for maintaining them a bit. But my legs, abs and lower back are weaker so 80% of my exercises focus on that. Works great.
If you are willing to press on, I wish you good luck. I am exactly like you, I view physical maintenance as nuisance and it's not easy to change the mindset. But I already started having that little little voice in my head that's sometimes nudging me to do a session because I know it makes me feel a bit better after.
In programming terms, I'd say reduce the size of the program/tests until it's manageable for you. My trainer said it's much better to train every day for just 35-40 minutes compared to two workouts of our and half a week.