This theory for love only holds up in a metaphorical sense. It does away with individual autonomy in couples and removes the individual from the relationship.
It is possible to be in love and remain independent. Two people can have different interests, values, concerns, fears, priorities and goals and still be in love. Respecting this individual autonomy can actually bring people together and make for a healthier relationship.
This view of love also fails to account for selfish agents who fall in love, who may not act in the benefit of the union but according to their personal interests and goals. Is this person not experiencing real love?
Alternatively, love may be unrequited or one-sided. Therefore, the union itself is not the love.
This view of love is particularly damaging for women. As women are encouraged by society to marry "up" and wed someone of a higher social standing than themselves, with a better job and a larger salary. When the 'we' is created, the dominant party will likely have a larger stake in the new identity. This often means the male in the relationship can assert dominance. If we want to establish equality in our relationships and avoid the overt oppression of women, we must abandon this union definition of love.