I can't comment on your ex's motivations, but I still hate to mix business and home or personal. Despite a number of coworkers encouraging me to date "at work" and the opportunities I've had (we have a lot more women working here than men), I have zero interest.
Actually, I have zero interest in dating in general right now. I told "G34" that I'm not going to the holiday party and so no date there. It seems a waste of time to date if I might be moving. Besides, my heart isn't here anyway.