Is a divorce pronounced after a threat of separation, should the wife not return to the marital home, considered one pronouncement or two, bearing in mind that the threat was intended as intimidation?

Your statement: "Each of us goes our own way" is a metaphorical divorce (kinayah talaq (definition)), which does not constitute a divorce unless intended. You mentioned that you did not intend it, therefore, nothing is binding upon you. Only the divorce you pronounced to your wife while speaking with her is binding. You may take her back before her iddah (definition) (waiting period) expires if this was the first or second divorce. However, if it was preceded by two divorces, she is forbidden to you and will not become permissible for you unless she marries another man in a valid marriage and he divorces her after consummating the marriage.