I think when you still have a lot of work to do in therapy, it's hard to conceive of a time in the future where we won't need that kind of relationship. But the general idea is that the more you heal, the more you come to know yourself, the less you'll need your therapist or others ( in that intense needy way). Your emotions will become more regulated, feelings won't seem so "big" and overpowering and the baggage that is behind those big overpowering emotions will be processed and diminished greatly. Eventually, you won't experience things in the future the way you do just now. And because of that you won't need the therapeutic relationship in the same way, if at all. And your friendships will be based on choice, not what they can do for you and whether they can replace the therapist or mother figure.
By the time you get to that point, in your healing journey, it won't seem so scary and actually freeing. Eventually you'll have a sense of inner calm and a way of being with yourself and fulfilling your own needs. It sounds lonely now because you're not finished your journey yet and can't imagine it but when you get to that place, you probably won't want to go to therapy, you'll want to get on with living.
That's not to say that the option isn't there to keep seeing a therapist, there's no reason to quit if you don't want to. I think as humans, we don't ever finish self-actualizing, trying to be better etc. The healing journey is never really over. But the stuff that weighs heavy on your soul right now won't always be so heavy.