I am also not giving "feel-good nonsense" advice, nor hand-waving. I'm suggesting avenues of research that require a level of effort commensurate with the task at hand, namely, creating a long-term stable relationship.
Statistically, relationships with the same attributes as my grandparents' relationships don't fall apart. Statistically, the most likely outcome in that case is "til death do us part". (You really should read some of JD Murray's books/papers. We can predict with a fairly high likelihood which relationships are going to lead to a split family and emotional/financial devastation for the husband, and which are not. But it takes a level of introspection and a level of honesty from friends and observers that most people don't have.)