Headswim - Your dream is a positive and helpful one, but before that I want to give you some information about what you said about the relationship.
What I am about to say is given as information - not a finger pointing at you.
What do you think it would be like to fall in love with or get married to someone who is only four or six years old emotionally? If you can’t remember being that young, love at that age means being incredibly dependent, with an enormous need for attention, possibly very jealous if someone else gets the love you desperately want; and if you lose a parent/loved one at that age it is devastating, even life threatening. But it may mean, because of early hurts, being unable to feel or express love.
An enormous number of us have not actually grown beyond the baby or child level emotionally. This means they have no realised that other people exist apart from them, and so can be very cruel. A baby has not developed a moral nature. That takes time and caring parents. See -
http://dreamhawk.com/interesting-people/animal-children/#ProgramAnother thing to be aware of is that it is quiet common for adults to feel intense and destructive feelings or jealousy about their sexual partner. This is exactly the sort of feeling we experienced naturally as a baby and child, but in adulthood we seldom see them as feelings that we have not grown beyond. Many aggressive or hostile feelings arise from childhood experiences, and are, at their origins, directed toward one or both of our parents. But unfortunately in adult life they tend to fire toward someone we have an emotional link with, such as our partner or even ones child. See
http://dreamhawk.com/relationship-sex/beware-of-love/ Now to your dream - it begins in an ideal setting and the sun is in dreams the source of your life, your energy. That you were in what felt like a childhood environment, suggests that your early years had some good influences planted in you.
You were then picked by a tremendous force/energy, but done so gently, and placed high up in a tree. A tree represents the natural forces of growth and also the roots of you and where you have grown form those family roots. The tree is strong showing that you have - again - good influences planted in you.
Then looking from this sense of your own strength and family connections you look down of an image of you ex partner and see how small he is - this means that you realise what a baby he is. You should learn from this and not treat him or any man who is actually a grown up baby as your partner. See
http://dreamhawk.com/relationship-sex/learning-to-love/ I know we put labels on people who do awful things, and I doubt he is a psychopath if his awful childhood were healed. But it is certainly wise to be in a relationship with any adult baby - they have a lot of strength and information about how to hurt.
Tony