can I place a note of caution here? I just don't like reading these posts which say leave him, he is doing this, he is doing that.
Firstly he has been kind in relation to the tragic miscarriage. When it matters most, he has been there.
Secondly, maybe just maybe there is absolutely nothing going on here. Maybe that is why it is hard for him to deal with/ find solutions. IF there was something going on, he really is not trying very hard to mask it. And, let's face it, as they work together and spend the day together, he really would be able to keep everything very clandestine with verrrrrrry little effort.
I have said earlier on in this thread that he is not being sensitive, I don't need to defend him per se. But it seems that no one is hearing what the OP is saying about herself and, reading what she says, she is really not in a good space at the moment, for the miscarriage, for the loneliness, for a number of things (and for which she is totally blameless and has my huge empathy and sympathy). But, it is fair to say, that these things may be affecting the way she is viewing the situation. If everything was just cool and she was feeling good about herself, she may have just laughed this all off.
I appreciate that some of you have been hurt in similar situations but I must repeat, not all of us men are cheating bastards. Many of us are good husbands, with flaws and qualities. I just don't think it is helpful to say "I was in an identical situation, get out".
And I do not think there is anything wrong with him talking to this colleague about his relationship. We all need outlets to confide in, it is cloud cookoo land to think that we do not talk to others about what goes on at home. Hell, we all do it here! Maybe just maybe there were things in his relationship which were not quite right and he has, over the last few months, confided in this work colleague. That is not a crime. And, in a flip side to everyone's attitude here, maybe she is not a predatory tart, maybe she is actually trying to help and support him. Maybe she could even be a positive help to his relationship. Maybe he told her about the miscarriage, maybe she was checking in to see how he was feeling. Maybe he feels he cannot show his wife how he is really feeling as he has to be strong for her.
All I am saying is maybe the best thing would be for the OP to be less fixated about this woman and concentrate on the big issues such as getting through the trauma of ger miscarriage, trying to find people in RL she can connect with and looking, together, with the DH at issues which are present in their relationship and ways they can work through them - rather than stirring up hornets nests, telling her to leave, telling her to intervene, telling her everything is bad.
Just my two penneth, from a daddymumsnetter...