When I don't believe in toughs, in abstractions, I can find anything and everything in myself. I am fluid. There is no fixed or limiting identity to measure my experiences or actions against.
It may be that there will at least be a trace of rigidity/fixedness as long as this awareness functions through a body and personality, but it is always possible to further soften this set of ideas called a self-identity. To soften it, help it become more inclusive and porous, until it melts away...
And there are many ways to move in this direction.
Working with projections is one. Anything and everything I see in the outer world - in other people, in landscapes, in dreams, in mythology, in stories, in movies, in the universe - all characteristics and attributes, are also there in the inner world. When I see a characteristic in the outer world, it can be a reminder to look for it in the inner world. It can be unfolded and experienced already, or it may be there only as a potential. Can I find it? Can I see that there is no difference between the outer and inner world?
Allowing thoughts to drop us is another. Allowing the belief in thoughts - in any thought - to fall away. Byron Katie's inquiry process seems remarkably effective for this. I experience a contraction or suffering, I find the thought behind it, and I inquire into it. Then it releases me.
Awakening to the nature of mind is another - or maybe that which makes all the other ones come to fruition. Here, I find a "ground" distinct from the small self, the body and personality, and all the habitual patterns of emotions, thoughts and behaviors. From this view, I see the inner and outer world as a fluid seamless whole. Nothing is fixed (or need to be), and there are distinctions yet no absolute boundaries. There is a sense of rich intimacy with any and all phenomena that arise in this awareness empty of any characteristics. This awareness experiences more directly, with less or no filters. Thoughts just appear within this awareness, distinct from the direct experiences. There is no need to believe in thoughts. They are just seen as that which they are - just thoughts. Just abstract representations of experiences. Very useful as that, but not anything I need to believe in or take seriously.
And living this, no matter how we come to it, is always a process. There is a continuing and deepening process of insight and integration. And life itself gives us feedback on where we are stuck, where there is still rigidity, where we resist experiences because they do not fit with thoughts we believe in. Suffering or dis-ease is a faithful and loving reminder.