Simple recipe for a successful long term relationship

Most of the time all relationships start with love! Most times but not all because I have seen relationships which start because of money or other “like” irrelevant shit involved. However, in the end what counts is that when the initial floury of love, excitement, and sex passes and life becomes a routine, and responsibilities come to play, how does this relationship evolves? Does it become a mature relationship where the parties in the relationship help and support each other and draw a common road map or do they begin to argue, disrespect, and ignore each other? In most cases the later happens and that is the reason I suggest that sex, even though important in a relationship, is not the most important pillar which makes a relationship successful and fun! In my opinion the most important attributes in a relationship are respect, honesty, truth, honor, support, and common goals. When people achieve these six principles in a relationship then I guaranty to you that sex will be wonderful, exciting, great, and crazy for life and not just for the first few months. If those six principles cannot be achieved then better do not have a relationship, better go pay for sex and go home without any worries (assuming sex is important to you)! Anyway, most relationships never achieve a comfort level, commonality, or the road mapping essential to building a successful and fun relationship. I have a philosophical question for you; how many couples can tell each other what they really think about their partner’s haircut, weight, dressing habits, cleanliness, intellectual capacity, opinions etc in a mature way where there is no fighting or bitterness? I will submit to you that the answer to that question is “Not many”!