There was increased literacy amongst the middle classes, and intellectual enlightenment when religious beliefs and traditional values began to be questioned. Romantic individualism encouraged the choice of partners for love.
As younger people undertook new types of work during industrialisation they often moved away from kin and community and were more influenced by their own desires.
There was still parental supervision over middle-class young women until at least World War One, with pressure to marry suitable partners. Illegitimacy and living in sin were stigmatised and divorce was unusual.