I wonder if you notice that you sound a bit confusing regarding one thing - you say you want to be separate, but that you are part of the host, but you want to grow more independent, but you want to integrate.
I don’t think there is anything wrong with staying separate, but I would encourage you to see it as your choice, not caused by trauma.
I identified as an inner helper - a child headmate who was exploring the mind and memories, trying to heal and help. However after a long time I did notice that unfortunately all of that was just building narrative that was just a cover for all the stuff that lied unaddressed underneath it. No matter how many carpets you use to cover the dirt on your floor, the dirt is still there. In order to fully heal you need to take the carpets out, face the dirt and clean it.
having a headmate is a great opportunity for healing, because if the headmate is loving and caring, the brain experiences self love, maybe for the first time.
However, that’s the only way headmate can help. All the hard work needs to be done by the host.
You have had bad experiences in life, you had terrible traumas in the past. You need to address your trauma and heal it - but don’t do it yourself, because it can be very disorganising. Go see a professional..
I know you said that therapists might not understand your spirituality, but I would encourage you to give it a chance.
I have been anti-spiritual my whole life, and my therapist actually helped me unblock that. I am semi-spiritual now, and I see that spirituality is a need of humans that can be very beneficial if addressed. My therapist understands it too, and maybe yours would, too. If you are worried about it, you might just ask them while booking an assessment appointment what’s their approach to spirituality, if they give an answer that doesn’t help you you can try someone else. Keep in mind that spiritual growth is not the cure, it can be just a way of putting another carpet on the dirty floor.