I see one of two things happening here. One is he was being disingenuous in his care during your time together and didn't care about you as much as you felt he did and had been putting up a front etc and, therefore, didn't comfort you in your time of pain. Another possibility is that he did care for you and has shut down his emotions about it as a way of protecting himself which comes across as cold and uncaring. I've seen this type of behaviour in romantic breakups where one person acts like an *** for whatever reason sometimes because they know what they are doing is wrong or terrible or whatever. I am not saying that is what happened as I wasn't there and I am not him so really have no idea but as an outside looking in it seems like it could be a possibility. Either way what he is doing/has done seems strange and is completely wrong IMO doesn't sound in any way ethical either.