Self-expansion model
The self-expansion model of interpersonal relationships proposes that people have a basic motivation to expand their physical influence, cognitive complexity, social or bodily identity, and self-awareness, and that the psychological reward from falling in love or an intimate relationship is whatever creates this "expansion of the self". Relationships are an important area for self-expansion, via a process called inclusion of the other in the self (abbreviated IOS), where aspects of a partner (e.g.