Kissing is often associated with youthful love. It is teenagers, and not parents, who kiss until they are weak in the knees on the escalator in the mall. You can be kissing another, watching others kiss, or experience that "I'm about to be kissed" moment.
Kissing another is often wish-fulfillment or sexual acting out. The wish-fulfillment may not be to kiss per se, but to experience the youthful energy of love. Kissing in this sense is the desire for the awakening of passion, not necessarily the passion acted out.
Watching others kiss may be a sign of knowing too much about them personally or participating in their lives at too personal a level. The exception here would be if you are watching your partner kiss another, which is an obvious herald of infidelity or a desire for voyeurism in the relationship.
The "about to be kissed" moment is an interesting one. Often, it occurs as we wake up. This is the dream that may most accurately reflect a desire for actual passion with another. The reason we wake up is the taboo feeling that perhaps, while we want this, it would not be beneficial to actually participate in it.
Is the kissing comforting or threatening to you?
Is it something you sought after, or was it forced upon you?
Is your general experience repugnant, romantic, or passionate?