If a man asks if you have anyone it means whether you live with someone. In this case, the man even more important is not the fact itself - married or not - but why you haven't married. Or not married anymore. Possible answer: I have very many fans, I just haven't given my heart to anyone yet.
If you were already married (or lived in a civil marriage) and you decide to tell about it, then in no case respond bad about her husband. It is better to say something like this: I was only seventeen, he would also be young, we are just completely different people. He is a wonderful person - everything is wonderful with him now, but together with us somehow it didn't work out.