But the fact that love can be experienced through sex associates them in people's minds. To "make love" is in fact a meaningful expression. And so with words like soul or spirit, people associate them with a symbolic context, such as heaven, angels, afterlife, and so forth. At the core of this is a legitimate experience, even if in their minds they are unable to understanding them beyond the context of the symbol.
This is why someone, say a Christian who uses a certain mythological framework, experiences the spiritual, they will associate it it with those beliefs. They validate the belief, and the belief provides a context for which they have their experience. They are fused together for them. In time, with a certain maturity, they can understanding spirituality found in many contexts, and the contexts are ultimately incidental to understanding the nature of the spiritual itself.
A young person views sex with their mate as love. And if the partner does not reciprocate for whatever reason, the immature response is "Don't you love me?". Or in the case of feeling spiritually disconnected, "Where are you God?! What have I done wrong?" In time, as we grow we become aware that love is expressed and known in many ways, and love as a word takes on far greater depth and significance. The same with "spiritual", where to the novice it means a shiny crystal or various religious artifacts. But there is a depth of understanding that loosens the associations like this. And so "the afterlife" really doesn't do all too much to speak about what is spiritual.
I really don't believe simply defining a word like love or spirit is anything that can be reasoned. It has to be experienced, and then its simply a matter of plumbing its depths and not being married to defining it at all. Poetry is a far better language to use, and dictionaries are quite poor substitutes for poetry!
That's because you have a different perspective. They don't have your context, and are seeing through the filters of their biology and culture and maturity. Again, the word isn't at fault. The stage of development is.
One of the things a therapist may do to show someone that love is not dependent on another is to have them think of that person and experience the love associated with them. Then they have them focus on the love itself, and remove the person from it. Once the associated person is removed, and they are still experiencing love, they become aware that love is something they already have independently from the trigger that evokes that for them. That is maturity opening up. That is expanding ones understanding of what love is. And so it goes....
Again, my whole issue is when someone says spirituality is a meaningless word because some people fuse it with things like crystal pyramids and channeling Chief Great Elk from the spirit realms. And whatnot.