There is obviously a sexual element in all forms of love.
Sexual love is also much more emotional than other forms of love, at least in adults.
The emotional attachment of adults to their sexual partners is much stronger than, for example, to their parents. As adult by an adult, you will never be loved fully if there isn't a strong sexual component in the relationship. Furthermore, I have found that there is a proportional relationship between the base level of sexual desire of a woman and her ability to love. Some are just easier aroused than others. And the most reliable tool to raise the level of sexual desire, not only of women but also of men, is language.