What is the difference between approaching the idea 'no-self' and the act to 'depersonalize'?

In modern days, 'de-personalization' is seen as negative and in some cases, a symptom of an emotional disorder. In Buddhism, seeing through no-self/identity view is the minimum criteria to attain the first level of enlightenment. These two concepts, seemingly similar; fundamentally, they could be different. Question: 1. Are these two the same or not? Shall they be separated or mutually embraced in our daily lives? 2. As a layman Buddhist, how can we approach this ?