Is it messed up that she's contacting my daughter while giving me the silent treatment?
I would say, yes it is. But only you can decide.
Speaking from my experience, I hope it may help you. Its a (slight) cautionary tale. Apologies if its a bit long! But it may give you some insight into possible future scenarios.
I went NC with my mother when my son was 11. She had been so abusive to me on this occasion that there was never any doubt in my mind that NC with me meant NC with my son. I think that was absolutely the right thing to do and I never gave it a second thought. Abusive to me, no chance to see my son!! Its about basic respect and protection of yourself and your family.
However, like you, I needed some support. I also had no other family. So when she got in touch just over a year later, we resumed contact. The next 7 years we got on fairly OK - I think partly because I had stood up to her and she was a bit careful with me, though there were still flashpoints and I had to deal with her annoying and rude behaviour at times. But luckily as we had moved 3 hours away we only got to see her 5 -6 times a year, which also helped a lot!
Then, another of her violently abusive outbursts 6 months ago. She gives the Silent Treatment and I go No Contact. This time round however my son is 18 years old! Now it is much more difficult situation. I am NC with my mother - but my son IS in contact with his grandmother. She has done some occasional smearing of my character. She told him I got inexplicably angry last time I visited her (reversal of the truth!). She told him under her breath that she is changing her Will (to exclude me was the inference!) . She has tried successfully to get some money out of him. She has made recently digs about him being gay (he's not). However, my son I think can handle it better than me, and says he can handle her and for me not to worry. I have warned him about her behaviour, he has even witnessed some of it (but not all of it going back decades). He knows what she is like in some ways, though he hasn't really had to experience the full force of her disorder. He is also slightly more protected because (a) they live so far away from each other and contact is limited (b) she is an old lady now at 83 and he is a teenager living his own life and (c) my son is a grandson rather than a daughter.
But I think you are right to say, that without contact with you, she will try to "up" the contact with your daughter, for supply purposes. This inevitably functions as some kind of splitting and triangulating, and so is likely to effect the simple and grounded foundation of your relationship with your daughter. It may be complicating and confusing for her to be "in the middle". So that is a real concern considering your daughter is still so young.
In my case in many ways it would have been better if we had stayed as NC when he was 11, as neither of us would have had to deal with any of this now. Now my son is 18 and has to make his own mind up and "manage" this relationship as he feels fit. However, I feel uncomfortable when he visits her for example, though I know he "has" my back and is too old to be influenced unduly by her. But I read some grandchildren ARE more easily influenced by a narcissist grandmother. I also unfortunately hear a few things back, inevitably, though he is not a "flying monkey".
However, I needed some support when my son was younger, even at a price, so I don't beat myself up too much about it. There is also those times when we seemed "like a happy family" and who doesn't want to try and experience that? However I was not supporting my mother financially in any way, in fact she was helping me a bit which was one reason we resumed contact (I was a broke, homeless and chronically ill single parent when she did her hoover 15 months after our row).
Finally, even 7 - 8 years ago, technology was less intrusive in a way. There was no face timing and my son didn't even have a smartphone. So it was harder for my mother to make "direct contact" and vice versa. Though she did chuck a bunch of cheap, badly wrapped "toys" outside our door one xmas for some reason.
However, if you do want NC for your daughter, it is possible. (1) you change her telephone number (2) you would have to explain to her - on a simple level that a 10 year old would understand - that your mother has been horrible to you and so you are not in contact with her right now. I don't believe that is "burdening" her with adult problems, in the way you were. It is just offering a simple, short, basic honesty which I think children appreciate and can relate to, especially if it is delivered in a mature, matter of fact way (obviously not emotional if possible).
I think a 10 year old who hasn't seen their grandmother that much honestly wouldn't miss them that much - at least thats been my experience. Children want their parents to be happy first and foremost. It is your decision, but if you do decide to go NC all round, I don't think you will be depriving your child of anything. Instead there is more chances for happiness and peace of mind for you, and your child will want that most of all (even if its something she can't know or express). I think you could definitely save that money you are not donating to your mother for you, your husband and your daughter to have some wonderful holidays together! Or for help for her starting out in life.
You are in a strong position in many ways I think, you have support and you don't "need" her help, and you also seem close to clarity. I hope my experience helps you in your decision. Its not easy I know.
Oh, just saw your update! See you have blocked your mother and given some explanation to your daughter.
