In any relationship, when we first meet, the feelings we feel for the other person will be transferential - either negative feelings or positive ones, or something inbetween. It can only be transference because we actually know nothing about that person. So the love we feel when it's 'love at first sight' or in those heady days of love that we feel when we first meet and 'falll in love' with someone is mainly transferential. We project onto the other person our idealised fantasies of who they are. Eventually, as we get to really know the other person, spend time in their lives, etc, that transference drops away and we start to see them for who they really are - and often it is at this point that things go wrong and relationships become messy and difficult - we will often hear people saying 'he/she isn't the person they were when I met them' - they aren't because the way we saw them was transferential.
Often though, when the transference falls away, we see someone we really do love and want to be with. It won't ever be heady like when we first met because we know more about them now and it has all settled down and is more 'normal'. Those relationsips are the ones that work. It might be that the two people involved are quite secure in their attachment s and the transference wasn't far wrong. But for many, especially those with attachment difficulties, the fantasy of who the other is and who they really are is way off. When we really find out who the other is it turns out they are more like someone who hurt us than someone who can love and care for us.
In the therapy room the same thing happens - we often 'fall in love' with the therapist - it is at that time transferential because we don't really know the therapist at all. But, this continues and the transference doesn't drop away so quickly - and that is what enables us to explore ourselves and better understand our past and what we replay in relationships. So, for sometime we are embroiled in an idealised transference and all the erotic and love feelings remain. It is important that the therspist holds the boundaries to allow it all to be played out, and the parts that went wrong can be re worked.
Just as happens in relationships 'out there', negative pathology eventually clicks in as the idealisation wears off - and feelings of love, hate, rage and envy come into play (depending on the level of early attachment damage) - and the therapeutic relationship allows them to be acted out and understood. 'Out there' it is likely this would be the point at which the relationship fails, but if the therapist is good enough, he/she will withstand and help to resolve these conflicts with the client. That is the job of the therapist, not to use the client as a potential sexual partner.
Unfortunately, due to the regressive nature of this type of therapy, it is very unlikely that trying to convert it to a real adult relationhip would work, because of the intense dynamics concerned. It often ends in the client being terribly hurt and a therapist losing his or her job. It's a recipe for disaster. I have read of such relationships failing disasterously - when the transference falls away and the reality of the relationship is far from the fantasy - and the client becomes powerless and enraged. A therapist who even attempts to do this is highly unskilled and unethical and has fallen into, rather than working with, the projections. It is abusive.
I don't believe, that while in such a powerful transference, we are capable of judging what is right for us, just as we aren't able to see things when we are in those first throws of love. Brain scans have shown that while in that state our brain is in a state similar to that of a psychosis - a losing touch with reality. It is therefore very important that the therapist can hold and maintain boundaries with the client to maintain a non abusive therapeutic relationship.
It's different, say, if a client saw a therapist a handful of times for CBT and there was no such transferential feelings. They meet up by chance 2 years later at a party and hit it off. That would be less likely to damage.
Moon