Project Everlasting is a new book that looks like a good one: two guys set out to interview couples who've been happily married for 40, 50, 60 years, to find out what kept them together. It's good advice, and seems to be well written.
Basically it comes down to commitment, tolerance, communication, intimacy, selflessness, appreciation, and respect -- all mutual. Heh. It's the "mutual" part that's a killer. You've got to be sure not only that you both are trying to communicate, respect, appreciate, etc, but also that you both are doing so in a way that the other person recognizes as communication, respect, appreciation, etc. Some people need a lot of romantic gestures, others find them a little silly. Some people are comfortable with vigorous bickering, for others shouting and name-calling destroys trust.
My ex-husband used to regularly called me "piece of shit" (sometimes "piece of fat shit", just for variety), and yet he was shocked when I left him! I know that to this day I still have a WTF reaction when my kids tell me that their dad thinks I'm intelligent, a good mother, pretty, or whatever. I've gotten to the point where I do believe that he thinks that, though, and even that he did think so when we were married. It's just that for him, insults could exist together with trust and respect. For me, they can't.
With
bbwoof, I've had to make a conscious effort over the last few years to respond to
bbwoof and not to any previous partners. Sometimes I need to remind myself. Sometimes I still fall into old habits, and old resentments. Sometimes I need to remember that he doesn't care about whether the dishes are clean or dirty, so filling the dishwasher doesn't need to have any emotional overtones anymore. But I also have to remember that what says "I love you" to him is being fed and kissed, while questioning his competency makes him feel unloved.
Maybe that's what makes a good marriage more than anything else: finding out what actions each other will interpret as "love" and "unlove", and being able to act appropriately.