Mistaking attachment for love is an easy thing to do. Mistaking addiction for love is also an easy thing to do. The two, attachment and addiction, seem to be intertwined or fruits of the same seed.
We may hold on to a thing because of our attachment or addiction to it, but it doesn't mean that the thing is healthy or right for us.
A drug may feel good, but it has deleterious effects and the feelings are short-lived. The same goes for certain relationships, such as the ones fueled by co-dependency or dependency.
How much we cling to a thing may serve as a litmus test for whether or not it is attachment, addiction, or love.
I'd goes as far to say that the things, particularly relationships, that are healthiest for us are things that do not cause withdrawal or pain during separation. In the first stages of love, we experience the fits of first love: the wanting, needing, lusting, aching. We must be around the other.
Later, as a deeper love comes through, the fits or highs of love subside, as the love/lust is no longer a thirst to be quenched or a hunger to be sated. Like Donne writes in "A Valediction Forbidding Mourning":
...Dull sublunary lovers' love
—Whose soul is sense—cannot admit
Of absence, 'cause it doth remove
The thing which elemented it.
But we by a love so much refined,
That ourselves know not what it is,
Inter-assurèd of the mind,
Care less, eyes, lips and hands to miss.
Our two souls therefore, which are one,
Though I must go, endure not yet
A breach, but an expansion,
Like gold to aery thinness beat.
If they be two, they are two so
As stiff twin compasses are two ;
Thy soul, the fix'd foot, makes no show
To move, but doth, if th' other do.
And though it in the centre sit,
Yet, when the other far doth roam,
It leans, and hearkens after it,
And grows erect, as that comes home.
Love can stand the distance; yet, dull love--such as lust, addiction, or attachment--needs constant attention. The feelings involved in attachment and addiction are heightened, erotic, and impulsive. The feelings involved in love are like a pervasive, quiet hum--constant in its regularity and continuity.
Relationships characterized by attachment and addiction are crutches or substitutes for something going on beneath the surface, perhaps psychologically. Where there may be emptiness or loneliness, relationships characterized by attachment and addiction come in to make full. However, these do not last, as they climax and come to an end, a kind of "coming down" from a high. These "users" are addicted to love and to the drama, passion, and excitement involved.
I'd say that love is not like the satiation that comes from eating a hearty meal, only to be hungry hours later. I'd say that love is the satiation that comes not from needing, but from already being full and wanting to give. It is characterized by reciprocity.
Because of this reciprocal exchange, constancy, and satiation, relationships based on love can withstand the tests of time and distance, as Paolo Marinetti so poignantly framed:
"Watching the distant darkening hills, the trees bending with the black weight of your absence, I think of you...and you are always with me, watching the clouds hurry over the dangerous waking seas, the islands biding their time like whales. Let us smile together, safe in our love that conquers distance, contented even in the bleak landscapes of separation."
I'll take Marinetti's words as prophetic insight into my love life: Though we are separated and, perhaps, have never even met, we can smile together, safe in our love that conquers distance, for we will one day be able pay homage to a love that has existed across space and time. And though our two hearts may break (in between our reunion), the larger heart we form will never break. It cannot be broken.