What is the ruling on dealing with the maid in the absence of the wife, knowing that she has been living with us for years?

Seclusion with a foreign maid is forbidden, based on the Prophet's saying: "No man shall seclude himself with a woman unless she is accompanied by a [male] mahram." If a man's presence with the maid in the house cannot be avoided, then a third party (such as the wife) must be present to prevent seclusion, or the maid should be in a closed room to prevent unlawful seclusion. However, if there is a fear of fitnah (temptation/strife) or suspicion, then it is not permissible to be in her company.