A teacher is personally detached from her students, and yet she lovingly teaches them. A nurse isn't personally attached to her patients, but she compassionately takes care of them. Similarly, if you dissolve your attachment to others, you can still be compassionate towards them.
A part of that compassion is to not apply the same strict standards of spiritual conformity to them as you do to yourself. Remember that they probably do not possess your level of enlightenment. By the grace of God and Guru, you have understood many spiritual truths, but this Grace has not been bestowed upon them as yet. For yourself, try to be totally detached from worldly relatives, but in your expectations from others, be understanding and kind, if they display attachment.
This attachment and detachment that is talked is an internal state of the mind. The fact that you are detached from others does not have to reflect in a distortion of your behavior towards them. A marketing representative has no attachment towards customers, and yet puts on his best behavior towards them. Similarly, even while being detached within, you can externally behave kindly and lovingly with others.
Having said this, a word of caution must be given. In the initial stage, when our detachment from worldly relatives is slight, it may be necessary to distance ourselves from them to some extent. Else, external sympathies may result in corresponding increase in internal feelings. If you do distance yourself for the sake of achieving your spiritual goal, it is not wrong.
