The living are allowed to want to carry on relating to the dead, but not just anyhow. When someone dies, the doors of the earth close behind them; they find themselves in the grip of a new current of forces, and they do not have the right to go back.
This is why we should avoid clinging to the dead and accompanying their departure with regrets, tears and wailing. So long as they have not passed the regions of the astral and mental planes, the distress of the living is a torment for them.
It is only when the dead reach the causal plane that nothing can disturb them anymore: it is as if they are in the centre of a magic circle of light, and no appeal or begging from the living can enter this circle if they do not want it to.
It is good to pray for the dead, to think of them with love, to send them light so that they may find peace and become free, but we must not cling to them.