God reveals the nature of love, having had written so much about it in His word. Therefore, we know there are four kinds of, or aspects about, love. Agápe, philéo, storgé, and eros.
Agápe is the base protocol, the carrier frequency of universe. Please refer to the links. If you do not have time, i quote from Insight: “A·gaʹpe, therefore, carries the meaning of love guided, or governed, by principle. It may or may not include affection and fondness.” And: “is wider, embracing espec. the judgment and the deliberate assent of the will as a matter of principle, duty and propriety.“
Philéo is the friendship love or affection. It can be felt for things as well, but that doesn’t interest us now.
Storgé is the natural affection, typical of blood ties.
Eros, though not mentioned in Greek Scriptures, is evidently romantic and sexual love.
How are all of these facets connnected together? Surely, they aren’t mutually exclusive. But I want to talk about the love a christian is supposed to feel and show for his or her spouse.
No need to say, the first thing, or better, the level-0 step is: being attuned with agápe. We can’t actually love anyone in any way if we don’t reflect this divine quality at our best. Doing so involves living, thinking and feeling in harmony with God’s personality. This has to be the vertex of our tetrahedron: the feeling in your spirit. And the others three follows, as subordinates.

We could take agápe for granted, yet it is the most difficult part. Anyway, marital love would be incomplete without the other aspects. Eros is the most immediate part, and it is indeed fundamental. But don’t underestimate the other two.
Philéo: it turns out that the “friendzone” is a necessary but not sufficient condition to achieve lasting love (unless you are bound to be indefinitely confined into it). In other words: your spouse has to be your best friend. I daresay: you can’t expect he or she will become such at some point. You have to build your true friendship before marriage. This gives me the feeling of special affinity, similar minds. The feeling in your head.
Storgé: affection is needed too. Careful: do not mistake attraction for affection. Eros tends to be invasive and to deceive our heart. This gives me the feeling of emotional affinity, similar hearts. The feeling in your stomach.
The more complete your tetrahedron, the more strong your love. Cute similarity:

The diamond structure is a tetrahedron as well. We can relate love to diamonds, of course. It appears now they share the same geometric structure. If love is properly built, they share toughness too, and are forever.
So diamonds aren’t overrated after all.
Song of Solomon 8:6:
“Place me as a seal upon your heart, As a seal upon your arm, For love is as strong as death is, And exclusive devotion is as unyielding as the Grave. Its flames are a blazing fire, the flame of Jah.“
Images credit: http://sciencesolve.blogspot.com/2015/09/diamond-structure.html