Often when therapists encourage attachment from their clients, it's not for the client's benefit but for the therapist's. A lot of therapists are extremely needy (based on my experience, as well as reading online forums) and feed off on the adoration of their clients. All this to say that perhaps your therapist hasn't encouraged you to attach to them? If that's the case, this all points to a good, ethical therapist. I also don't believe that getting attached to a therapist is somehow a healthy sign for a client. So not being attached does not make you broken at all.