If your single friend doesn't know you well enough to give you advice about your marriage then he really doesn't know you at all.
Your error is you are not recognizing that we can have communicable objective knowledge of what is subjective. For example, we can understand the death of someone's parents and offer valuable support for those grieving even if we have not personally lost our parents. It is not necessary to first go through the experience.
There is a sense in which something subjectively experienced cannot be effectively communicated, however, this is only in the case of that which is specific. Knowledge of your particular marriage cannot be had by anyone except you and your wife. However, this does not mean that one cannot have knowledge of the subjective nature of marriage- simply that they cannot have knowledge of the subjective nature of a specific marriage. This knowledge is not only innacessible to non-married persons, but to anyone except you and your wife.
On the other side someone that's never been in a committed relationship can't relate to the everyday troubles of those who are. And there are very few things in life that have any real similarity to marriage, some form of equivalency a person can use to relate. And none of them are on the standard path to becoming a priest.
On the other side someone that's never been in a committed relationship can't relate to the everyday troubles of those who are. And there are very few things in life that have any real similarity to marriage, some form of equivalency a person can use to relate. And none of them are on the standard path to becoming a priest.