I would like to think that the sky is the limit; that two people can get so close that they can reveal themselves, perhaps not in entirety, but close enough.
We keep secrets from one another, don't we? We keep the secrets that we must. We shelter the other not just from parts of ourselves, but from parts of themselves. We understand that complete disclosure wouldn't be in anyone's interests.
What happened in childhood, the attachment issues that may have appeared back then, potentially even in the preverbal stage are enduring. They leave marks on the psyche. It's territory that should be explored only with a well-trained therapist, not a partner, so sometimes one just adapts and makes allowance for, and compromises with a partner, in the overarching interests of what is.
I do believe that an attachment style is able to be adjusted; that is, that one can go from an insecure attachment style to one that is secure. I am testament to that.
I have taken a test a few times to ascertain my attachment style. It focused on asking me questions about my mother, my father and my husband. I came out as having a disorganized attachment style. In one case, I was said to be 'avoidant' with similar questions. But I noticed just yesterday when I was whiling away time awaiting the cooking of the vegetables that the test score revealed I was actually quite close to the category of secure if you took away the result of the attachment to my mother. It was the result of the relationship with my mother that had statistically reduced my overall score.
I suddenly realized how flawed this logic was. Sure, no doubt, I needed to look after myself as a child whilst, of course, wanting to be nurtured, but should that affect my functioning score now? So, I went elsewhere and immediately noticed that there were no questions about my parents - one dead for over 30 years and the other one at death's door - bur rather lots of questions about my thought patterns and daily patterns now. What do you know, I came out as Secure.
This was delightful news and signified buckets of growth. I have been feeling it, especially recently. It comes down to those few words - It is what it is. Acceptance.
It's really important, I believe, to have plenty of empathy for the people with insecure attachment. Sometimes they are obvious in their presentation but often they are not. Even well trained and highly experienced therapists need months if not years to figure them out, so it's not so much a job for us to figure them out, as it is to accept that there is some trauma there.
Try your best to stay emotionally regulated yourself. Stay calm. Maintain appropriate boundaries for yourself. When you hit their brick (emotional) wall, and you will feel it when you do - recognize you have gone as far into that neck of the woods as you can today and let that expedition go. Only ever do what you can do without there being harm done.
No matter what defences a person puts up, we are all fundamentally the same in that we all want to get close. Sometimes, people just don't know how. It just doesn't feel safe. You do what you can do. It's all we can do. There's peace in knowing that.