I stopped dissociating a couple of months or so ago....just seemed to happen completely out of the blue without any warning, so it was quite a shock.
I'm not really sure exactly how it stopped...!
Grounding techniques were useful. I found a couple of things worked particularly effectively, so I used those a lot - spraying/sniffing perfume, putting on hand cream and washing my hands in cold water. So smell and touch seemed to be the senses that responded best to stimulation to get me present. Might be worth experimenting because you probably have a preferred sense as well, which will work better for you than others.
Also agree that it helps to really force mindfulness where you can - and there will be plenty of times you won't want to! But dissociation can so easily sneak up on you and if you don't catch it and act early, that could be a massive chunk of time lost! So I used to regularly check in with myself. Which sometimes meant setting an alarm to go off every hour - or even half hour - during the day to just check I was here and that I could feel my feet etc. If I then realised that I felt spacey, I'd spray perfume, go and wash my hands, get up and stamp my feet, play a favourite song loudly etc. And I used to set a timer for half an hour when I had a bath as I often used to 'go' in the bath too - used to suddenly realise two hours had passed and I was sitting in cold water!
I think a key thing was - I also had to put myself into a potentially very triggering situation/environment earlier this year and that was a really big deal for me. My therapist and I worked on it together for weeks in the run up and we did a lot to help me prepare. Most of that preparation work was focused on my boundaries - it was important that I felt safe, felt in control and that I stayed present. At the time, I thought my therapist was being a bit OTT! In reality though, I did manage to have the most positive experience I think I could have had and I didn't dissociate during the situation. So, I think the fact that I felt prepared and the fact that I had plans that put other strong boundaries in place and the fact that I made a huge effort to be mindful and stay present meant that my default boundary setting (dissociation) didn't kick in. My therapist kept saying afterwards how much I'd achieved and, again, I thought she was being OTT. But now I can see that it did pretty much coincide with dissociation disappearing for good, so I guess she was on to something! So I think maybe something in my psyche thought that I didn't need it anymore because I had other things to use.
It's a tough one and it is hard work. And, to be honest, it's still a tough one. Having dissociation disappear so suddenly is pretty uncomfortable as dissociation obviously protects us and keeps us from feeling things. Suddenly feeling things and not having dissociation swoop in to 'save me' is very, very hard. Also, my boundaries have become an even bigger issue than they've ever been....I think this is probably another layer of defence which has ramped up in the absence of dissociation. And I'm finding the boundary stuff a real struggle at the moment. It's causing a lot of anxiety...but my head doesn't check out at that point anymore so I just have to sit and feel all the anxiety. Ugh!
So...keep the faith...dissociation absolutely can be beaten. I couldn't have done it without my therapist and also without putting in a lot of hard work myself. And I'm certain that the prep we did before the triggering situation was really key to something in my brain realising that perhaps I didn't need it anymore. But also be prepared that, if it does go, that's just a whole other stage of stuff to work on. Because then you can't completely shut down from the uncomfortable feelings in the same way. And you may well find - as I have - that you have a few layers of other defence mechanisms underneath the dissociation...so that's more work to chip away at each of them until they dissolve too!
Sorry - this is such a long post! It's a very fresh thing for me at the moment so is very much on my mind. It does seem to be a long, long road. I'm sure it will be worth it in the end. It has to be, right?! ;-)