Sorry this answer is so long. I just wanted to address your main points as I can relate to much of this.
So, my narcissistic, gaslighting, stonewalling, master manipulater mother and enabling father turned up unannounced yesterday - Oh yes, I recognise this.
I've learnt to deal with them by being civil and not emotionally involved so they can't pull my strings - Wrong. I have no emotional attachment to them. You clearly do. They do pull your strings (else you wouldn’t have posted) and you haven’t learnt to deal with them, you’ve simply learnt how to appease them in the hope it all sorts itself out? Spoiler Alert: It won’t.
She has no relationship with our child who is three...When she saw it was them she ran off and hid in the living room crying - Your child has learned/is instinctively aware that this/these humans are ‘bad’.
Then when they came in she continued to cry so Grandma said look at what I've bought you...She reluctantly took the chocolate and stopped crying. Reluctantly. That’s the significant bit here.
(internally I shook my head, but I'm conditioned to not challenge her). Uh-huh. I hear you.
We try to have civil conversation, but my child is sat on me and making sure I don't leave her and crying. Again, your child instinctively knows these humans are ‘off’ and needs the safety of Mummy.
When they said they were going my child stood up gave grandma her bag and went and opened the front door. She said bye and shut the door behind them. Your child is literally trying to protect YOU. She did the right thing. She isn’t constrained by social rules at this point AND hasn’t undergone extensive conditioning - yet... Something to think about - because if you don’t take action and end this, she will.
After she left I noticed Grandma had taken her chocolate that she bought her. So? You’re surprised?
Am I being unreasonable to be letting this irritate me. Yes, yes you are - because you KNOW this is a game
I know my child was rude by adult standards No, not even slightly. She’s actually the only one here trying to make it stop/trying to protect her Mummy.
but no need to take the chocolate back!... I should learn, but this time she is messing with my child. Absolutely. That’s exactly what’s happening here.
I did try no contact, but it broke my heart. I settled on civil because it's where I feel the least distress. - No, this is causing you a lot of distress - and it will only get worse. Your heart is broken because you’re grieving. You grieve the loss of the relationship you SHOULD have had, how your life SHOULD have been. Grief counselling/literature is likely to be extremely helpful to you, if you are unkeen on seeing a therapist directly.
I have considered moving to put at least a 1.5 hour drive between us - pointless. It doesn’t solve the problem.
I tried therapy and they suggested no contact - your therapist is correct.
I know my mother, if my child had behaved favourably towards her she would have left the chocolate. She conditions people. That's how she operates. You will be punished if you don't respond how she wants and you will be rewarded if you do - again, Oh yes. I recognise this. You’re absolutely correct.
My child was not crying to get a chocolate bar. She was crying in a way, which was saying I don't like these people in the house - Yes
God I need to get out of here - No, you need to get out of this situation
I do realise and made all the more clearer from these responses that it is my job to protect my child from this mess - 100%. Because right now, your child is protecting you...
This passive, I've given up, do what you want and I wont emotionally respond is not working either - again, you haven’t learnt to deal with them, you’ve simply learnt how to appease them in the hope it all sorts itself out. However, your child struck a clear blow today, as demonstrated by this: My dads just phoned up, which is extremely random because he never calls (and by that I mean he NEVER, ZERO) and rewrote the narrative. He basically rewrote history that my daughter was poorly and just woke up so was upset when they visited - again, YOUR CHILD is protecting YOU (and this time it worked - today you won, well, your child did) - again something to think about...
For the record, five years ago I told them I'd had enough and was going no contact...Slowly we have settled on a civil relationship without talking about why they have hurt me, because they wont - no, slowly they wore you down, to get everything back on THEIR terms
I presume they have chosen against therapy as they won't be able to hide their abuse from the family therapist. It will just be confirmed - no, it’s simply because she/they will refuse to accept responsibility for any of this, rendering therapy pointless
I'm not sure I need therapy. I've gone through the grief of not having the parents every child deserves - yes and no. It would be healthy for you if just to help clear some of these toxins from your heart. But I disagree with ‘every child deserves’? Sadly the world doesn’t work like this (yes I know we live in the Age of Entitlement) but it’s still all about how the dice fall. At this time, you cannot have the Mother you dream of, but you do have other worthwhile relationships in your life. Feed those ones!
I just think the only way now is to physically move so the contact is just reduced to funerals and weddings - no, go completely no contact, because they have already proven they can force you back into contact on their terms whenever they like (you’re going to disagree with this, probably strongly but I am right)
She clearly hasn't changed one little bit...and it's now starting with my daughter - Yep. See last answer ^
I hoped they could be good grandparents in a low contact kind of way - Not at this point/under these circumstances. Good pipe dream tho.
I felt it wasnt my place to alienate my child from them - WRONG, WRONG, WRONG, WRONG, WRONG!!!!! (Sorry, I don’t mean to be harsh)
I actually don't want to talk about it. I'm exhausted by it - Aye. And it will continue to exhaust you... this isn’t going away. You have to deal with this, now.
You’re experiencing terrible grief and you must focus on dealing with that FIRST. It is essential to go NC in order to achieve this. And it may take years. Frankly, that doesn’t matter. Take all the time you need. And right now, your child will be fine, as she has not been exposed to much of this.
Only when you are feeling strong (ie when you are able to directly challenge every and all behaviours you don’t like) and have fully accepted that you’ll never have the parents you so desperately want (so when the grief is gone and/or filed away neatly!) can you even start to open a dialogue with them with the possibility of reintroducing them into your life. But it must be strictly ON YOUR TERMS. If they can’t accept that, that’s genuinely not your problem (and could be a blessing in disguise). They are adults, but you’re also an adult; and that makes you equal - remember that. Good luck.