Other than physically, is exercise equally beneficial for all people?

People talk so much about the psychological benefits of exercise and how once you get into it your mood, sleep, and attitude change for the better. People even say once they exercise on a regular basis they feel awful if they don’t exercise.

My issue with this is twofold: 1. Human beings are varied. For every human that has a certain experience there is another who does not have that same experience. Not everyone can see certain colors, so why would everyone’s body react so positively (other than physically) to exercise? 2. Personal experience. I have started and stopped exercising so many times I cannot even come up with a number. I usually go a month to six weeks before I stop. The thing is, I never get that high everyone talks about. I never feel like I have more energy, my sleep does not improve and I certainly do not feel bad if I skip the exercise.

So, am I not giving it enough time? Am I doing the wrong exercise? Why don’t I get the benefits everyone talks about? Can it be that not all people will get the added benefits of exercise people seem to think applies to everyone?