The Russian Greatcoat

Theodore Deppe's poem "The Russian Greatcoat" portrays a family man reliving his past. I can assume that the "mystery woman" as she is never named, is an old lover. Deepe is a seemingly good man "At first I evade the question when my wife asks, as if just thinking of you were an act of betrayal". I would draw from the passage that "mystery woman" is a beautiful woman, a somewhat bossy woman. Deppe seems as if he would do anything for this woman. I am brought to the question as to why he must only think of her, why didn't the relationship assuming there even was one, work? Love lost is the topic, even while married with children he can still think of "mystery woman". Was she the one who got away? Deppe seems somewhat hear broken "sometimes i can go weeks without remembering". What was so great? Why is she a reoccurring thought through his head? Leading me to believe she is the one who ended it. Is he happy in his marriage? Deppe focus's on those moments, maybe because that can tell us all we need to know. They were not together no longer, and he would do something so irrelevant just because. That maybe their relationship was not a good one, maybe she was controlling. But why would he still reminisce on old times? What was the reason for the ending of the relationship? I want to know! Why can he not get her out of his head? Does his wife know about her, is that why she might become angered by the idea of her?