Yep!

The first thing people notice about other people (esp. strangers) are their looks. However with constant close interaction with that "attractive person", people can't help feel but get used to his/her looks making them slightly less attractive.

Plus, the issue of one's attitude which greatly defines a person and trumps his/her physical features. Someone physically "attractive" to many but with a very bad attitude is at no surprise not that "attractive" to many after some time.