Are monks better teachers than ex-monks?

It seems that most of the dharma teachers in the West are lay people, as opposed to Asia where most of the teachers are ordained monks. Many of the western teachers were monks for a while, but decided to disrobe. My assumption is that these teachers are not enlightened because they usually get in relationships after disrobing. My question is, is it wise to follow these lay teachers, or is it better to wait and try to find a monk who has made a firmer commitment to the dharma? I'm not trying to be disrespectful, it's just that it seems like the act of disrobing is sort of a rejection of Buddhist teachings.