Romantic love is an addiction: a perfectly wonderful addiction when it's going well, and a perfectly horrible addiction when it's going poorly.

As women in industrial societies join the paid workforce, they gain the economic means to depart unhappy marriages more easily.

If two very different people pool their DNA, they'll create more genetic variety, and their young will come to the job of parenting with a wider array of skills.

There were real reasons that you were attracted to somebody originally. The brain doesn't pick willy-nilly. Unless you part ways hating each other for some reason, that mechanism could get triggered again. You can literally fall in love again.

Women are naturally prone to compete over their mates.

Romantic love is an addiction: a perfectly wonderful addiction when it's going well, and a perfectly horrible addiction when it's going poorly.

Men have a psychological need to show off their courage and strength. When he sees you talking to another guy, that instinct kicks in and he jumps to protect you and prove he's worthy of your love.