Dear Concerned,
Your situation confronts many men and women in our present society. How do we maintain appropriate boundaries with each other in an environment where we come into close contact often? How does a couple trust each other in a world that is fallen and may have different values from us?
It is sad to hear that your feelings of discomfort were dismissed by your husband. As an adult and a man, I can see how he may be upset if he felt that you were being very controlling. So let me ask, just to be clear, if you have been questioning his every decision and insisting that he gets your approval in most instances?
Assuming your answer is no, does he understand why you are uncomfortable about these interactions he is having with his female colleague? I can see at least two reasons for your heightened concern. Firstly, it involves having frequent one-on-one interaction between the two of them. Even if he does not have any dishonourable intentions, what about her? Also, others noticing their coming and going can get the wrong impression of the nature of their relationship. Finally, your husband’s kindness could be misunderstood by the colleague’s husband, if she is married, and cause tension in their marriage.
Secondly, these interactions only came to light because you discovered it. It was not volunteered by your husband. Even if he did not mean to hide them from you, it shows that he does not understand how you might feel about such interactions. I wonder if he had kept you informed and even told you more about this female colleague, he would have demonstrated respect for your feelings and that there might have been no cause for anxiety on your part.
Perhaps, a calm conversation would be a good way to clarify some of your concerns and his needs. If the relationship between the two of you is still too strained, a trusted friend can serve as a go-between until such time when you could both talk about it yourselves.