For most of us, wisdom is acquired in the thicket of experience and usually meets us somewhere along the way if we live long enough. But sooner is better than later.
Remember that no relationship is a total waste of time. You can always learn something about yourself.
Remember that life's big changes rarely give advance warning.
Tell your wife often how terrific she looks.
Be smarter than other people, just don't tell them so.
Life doesn't require that we be the best, only that we try our best.