Depends on the person you speak too, since everyone has different interpretations of love and sex. Like some others have said, sex doesn't necessarily equal love - and I tend to agree. However, sex can be emotional and help a couple form a tighter romantic link or emotional bond because of the state of vulnerability that sex can leave you in; but it helps if you already had/have those feelings in the first place. They tend to call that, 'making love', which is an emotional and romantic form of sex. Others just have want to have sex to feed an animalistic need and will only ever see it that way. They usually equate love directly to other actions such as; purchasing gifts when they don't need to, and doing things for you they wouldn't normally do for someone else. Such as running your errands because you are exhausted and throwing you a surprise Birthday party, or some such thing.
As for monogamous, polygamous, and open-relationships; as long as there is communication between the partners and couples, there really shouldn't be a problem and I am not opposed to these forms of relationships. I am not opposed to a couple who have talked and want to remain monogamous, as long as both realize that both probably still find members of the opposite sex or same sex attractive and may even *gasp* have lustful thoughts over someone else. Really, it seems to be the jealousy for frivolous things and open communication that seem to hurt monogamous relationships the most. When communicating your thoughts and feelings openly should be what makes the relationship strong and increase it's longevity and trust.
