In marrying, bride and bridegroom are informed that it will henceforth be their 'duty' to love one another, although, since love is an emotion, it is not subject to the control of the will and therefore cannot come within the scope of duty. Considerate behaviour may be a duty, but love is a gift from heaven: when the gift is withdrawn, the one who has lost it is to be pitied, not blamed.
Source: "On expected emotions" [From: Mortals and Others: Bertrand Russell's American Essays, 1931-1935, v.1 (1975)]
More info.: https://russell-j.com/EXPECTED.HTM