Do the angels leave a home if a Christian woman is invited for dinner, or if she brings a dog with her and returns to her home, do the angels then remain absent for 40 days?

A dog prevents angels from entering a house, based on the Prophet's (peace be upon him) saying: "Angels do not enter a house in which there is a dog or a picture." As for the duration mentioned in the question, it has no basis. The entry of a disbeliever into a Muslim's house does not prevent angels from entering, and "the carcass of a disbeliever" refers to the body of someone who died in disbelief. A Muslim should only associate with a believer, and only a pious person should eat their food, and "A person is on the religion of his intimate friend, so let one of you look at whom he befriends."