Comparison based gratidute via /r/gratitude

I'm trying to be grateful and because of it I started questioning if I'm allowed to have any dreams, because I have shelter and a clean water, or should I just settle and be happy with what I have. Today I started calculating the probability of having all ilnesses I have combined and it's less than 1 in 1000. I felt relief that finally I'm allowed to dream bigger, because I'm on the side of population that has worse life than most. Now I'm thinking – is it healty to have this kind of attidute? Intuitively I feel there is something wrong with it because most grateful people don't do this kind of calculations.