How to Love Well

The other day at work a man in his 70's came in, and mentioned to me that he is getting a divorce. Last week, a woman, who was also older came in, and was in the same situation. In fact, a lot of people come in buying furniture and volunteer to me that they are in the middle of a divorce. Surprisingly, a lot of them are older, and have been married for years. This combined with some other things have made me wonder a lot recently - why do some relationships last and others don't? One of the simplest answers I've ever received regarding this was from my work study supervisor in Kona. He told me, very simply that "Any problem in any relationship can be traced back to one thing - at least one person is not right with God." I see his point and agree, yet in the "messiness" that is life, what does that actually mean and look like? Why has a man in his 70's not yet learned to be loved and to love well? Why do relationships ever end? And for that matter, what even makes them begin with select people? I personally don't believe in "soul mates" and I think "chemistry" means nothing. So is it just commitment? Surely it can't be, because even then, how many relationships are virtually "broken up", but just legally called "married"? What makes a relationship "good" or "bad" and who decides this?