scared of more people who know me from work wanting to ask about my life

I like most of my customers but they know that I was in a serious relationship and that we were committed and talking about marriage and now I'm scared they will ask how its going...I'm at work I don't want to be reminded of my loss and don't want to be sad there. How do I avoid this situation...I'm starting to think it must be easier for him than it is for me...just silence...feel weird about talking to people at work and hope they don't ask.