1- Rocking in dreams can be a comforting activity; a little like a child who will rock himself to sleep. Rocking can also suggest infantile behaviour from the point of view that it puts us in touch with the natural rhythms of life.
2- Particularly when we want to be soothed we like to be rocked.
The gentle movement can allow us to be in touch with our own centre. So to be rocking someone is to be soothing them. Conversely, to be rocked is to be soothed.
3- Rocking is a symbol of transition.
To move to and fro suggests both hesitation and desire. Rocking is also a fertility symbol.... Ten Thousand Dream Dictionary
To dream of a rocking horse foretells happiness with friends and family. It may also suggest you are trying to hang onto childish pleasures, as life starts moving quickly for you.... My Dream Interpretation
Oswald (as related in his book Sleep) observed active rocking in some children and adults during sleep. These rocking movements were very powerful, occurring at a rate of one per second during REM sleep. They occur more frequently in the blind or to people institutionalised during childhood. As rocking is a movement used by primates and humans to comfon themselves during stress or unhappi- ness, it is possible that the rocking accompanies disturbing dreams.
The dream probably evokes unhappy feelings or conditions from the past, as the person used rocking to cope with their past distress, it occurs as an habitual accompaniment of the distressing dream. ... A Guide to Dreams and Sleep Experiences
Vision: Sitting or swinging on a swing: you are too easily influenced by others, have a hard time making decisions and, generally speaking, may be fickle and sometimes downright unreliable. Looking at a swing: it is time to look at your inconsistency. Rocking on a rocking horse: you are frittering away your time; also, what you call love is really infatuation.
Depth Psychology: A swing means your moods are constantly “swinging back and forth.” In a man’s dream, it also might imply that—if married and having an affair—he can’t decide between his wife and his lover.
The dream is a warning: make a decision now and be more assertive.... Dreamers Dictionary