The spacey, trancey, zoned out experience of dissociation is certainly an easy, safe place for me to slide into, especially in therapy. It's like being in a comfy, protective bubble a million miles away from everything and everyone else. What's not to like?! ;-)
When it goes too far and I reach the point of not being able to feel my body at all - so I can't stand up because I can't feel my feet or I bang into things because I can't work out where my body is in relation to objects etc - I guess that becomes potentially unsafe though I don't think I realise that in the moment as my head is too far gone by that point.
I suppose the main thing I've come to realise is that dissociation is a defence mechanism so it shows up for a reason. I do generally try to fight it when it happens in therapy but sometimes it just feels too hard so I think there is an element of giving in to it. But if I give into the spaciness I'm in danger of getting to the shaking/can't stand up stage, which is potentially dangerous. And whether I'm a bit spacey or full-on gone and shaking, if I'm dissociating at all, I'm not fully present. And if I'm not fully (or, at least, significantly) present in therapy, I can't really do any work, so it really just puts a stop to the session, even if I continue to sit there.
So, not being present in session and not being in relationship with my therapist and not being mentally/physically/emotionally engaged means not doing any work, not making any progress, not learning anything, not really accomplishing anything of any value at all.
A few questions for you to ponder if you want to:
What is it that makes you willingly dissociate and reluctant to try very hard to get out of it?
What is dissociation giving you?
What might a session be like if you didn't dissociate?
What might be difficult about a session in which you didn't dissociate? What could potentially be gained by a session in which you didn't dissociate?
I find it hard to get the balance between accepting and respecting that the dissociation is there for a reason (to protect us) so don't try to force it away if it's doing an effective job vs taking responsibility for trying to push through a bit and not just let old habits that may not always serve me well now take over.
And I totally agree with
@NightSky about dissociation protecting us from feeling our feelings. Do you know what specifically yours may be protecting you from? I think, for me, the big feeling that I can't seem to "be with" is shame. That was a fairly recent revelation for me. If you can identify what you can't be with, that may be a useful step?
Not meaning you have to answer any of the above questions here, of course! Just putting them out there in case they're of use but they may well not be!
Just to add - how is your relationship with your T and your level of trust/safety with your T/the therapeutic space? It may be that your dissociation (and your willingness to go with it) are signs that you need to build more trust/safety with your T, that you need more resources in terms of grounding, that you need to work more on stability, that you need more support in place beyond your T (friends, family etc) in order to have strong enough foundations in place to enable you to really go there etc. Perhaps the work is moving too quickly and you're just not ready yet? In which case, very understandable that your head just wants to check out. I'm sure loads of us here can identify with that. I certainly can!