Good morning everyone and thank you so much for your supportive messages.
I haven't replied properly for a few days, as I was just feeling a bit overwhelmed and exhausted by everything. It was useful to have the specific bereavement therapy, which seemed to home in and target things very effectively. It was a first session, but the counsellor picked up that the issues with DD1 are having a detrimental effect and regarded my grief as more complicated, as it is like a double bereavement. She also thought that DD1 might have a personality disorder and advised me to step back, said that grief is exhausting, and that it is fine not to do too much and to have a 'duvet day'. She made me feel that what I am going through is normal, indeed she said as much. That, in itself, made me feel a bit better, that I have 'permission' to do nothing, although I do try to do some things each day, even basic things, so that I don't go to bed feeling that the day has been totally wasted.
In réponse to various comments, yes the book was the 'Gulag Archipelago' by Solzhenitsyn. I don't think that it was intended to be cruel, although it was certainly insensitive. LB was reading it at the same time and thought that it was interesting, so they decided to buy DH a copy. LB sees himself as an intellectual and DD1 seems to hang off his every word, so I suspect that the suggestion came from him and that she just went along with it. She was surprised when I said that I was already familiar with it, as I had read it many years ago.
I had assumed that they gave DH a second hand copy as it was out of print but no, it is readily available on Amazon. For DH's 59th birthday, they gave him a 60th birthday card and a cheap wooden picture frame containing some photocopies of pictures of DH and DD1 together. It's not that I or DH wanted anything expensive, and indeed he was always grateful for everything, but it's the lack of thought, that they got the year wrong. For my 60th birthday, I received a card three weeks after the date and DD1 hadn't realised that it was a significant date (maybe I look young for my age 
). And these cards would say 'We hope you have a relaxing day' and signed by them both, no love or personal messages like I receive from DD2 and DD3, but the sort of cards and messages that you would send to a distant relation whom you never saw - maybe that's how they see us.
What does LB do all day? The answer is, so far as I can ascertain, not very much. He has a 'workshop' with various tools, such as lathes etc and starts lots of DIY jobs, which seem to take forever to finish. In the meantime, DD1 is full of admiration at the performance of these manly tasks and takes on all of the childcare, cooking, cleaning etc. I think that she was managing whilst there were two DC and she was not working, but she has found it exhausting juggling all this with studying and teaching. When it all becomes too much, they usually rely on LB's mother to step in. For example, when DD1 was doing a compulsory on line course for a week, her MIL kindly took the DGDs for four days but, on the 5th day, when MIL wasn't available, DD1 had the DGDs with her and just had the course on in the background. On one day last week, when DD1 had a big backlog of marking and coursework, MIL again took the DGDs for the day. DD1 told me that she is like a 7/11 shop because she is always 'open'.
I am so pleased that some of you think that I actually did the right thing by expressing my feelings, as I was kicking myself for having 'blown' the reconciliation. I am just so afraid of being hurt again. I tried to explain this to DD1, saying also that I was struggling so much with the loss of DH, that I was 'literally at the end of my rope'. not really well or coping terribly well, having therapy etc. But it just seems to wash over her, it doesn't make any difference, she won't make any allowances for me. No matter how hard I try to open up dialogue and tell her that I love her and want to work things through, she just explodes and becomes angry, then says she needs to speak to LB, who of course is not my biggest supporter. I sent her a short message on Monday just wishing her well, as she had an assessment, but there has been no reply, of course.
Thank you Lockdown and all of you for your wise advice and, also, to Sssloou, whose has an uncanny knack of seeing right inside my head and who has been a massive support to me, as you all have. Please note though that I am happy to receive criticism as well, because I feel that if I knew what I had done wrong, I might be able to fix it. Part of me thinks that I was wrong to get upset about not visiting on DGD1's birthday and should just have gone the next day, that I have 'soured' it all. But I was feeling that I would be alone and vulnerable and hundreds of miles from home, so wanted to try to clear the air first. However, I think that one of the previous posters was right in saying that I will probably never know. Basically, I need to come to terms with it all, but it does make it hard to reconstruct and rebuild. And I know that DD1 is under a lot of pressure at present and the last thing I want to do is to add to it. billy, I hope that you are right and that DD1 will process things, maybe when she has more time. She doesn't understand why I, and her sisters, can't just pick up where they left off. And she has been making an effort to be in touch and change things going forward, so maybe I was too harsh. It has all just been a bit too much on top of everything else. The bereavement counsellor says that my anger is natural and part of the grieving process.
Justilou, there hasn't been a miscarriage, not as far as I am aware anyway, although I wonder if she would tell me now and, of course, I am worried about her. Thank you so much, and to everyone, for your kindness.
forrest, it is interesting that you use the words 'fake relationship', because that is how it feels, what my therapist describes as not 'authentic', which I personally find very difficult to deal with right now.
Concepta, I am very sorry to hear that you and your DP have experienced a similar situation. It's soul destroying, isn't it? I think that you are spot on in saying that whereas there is energy in your 60s to deal with this type of thing, the risk is that we become more vulnerable as we become older. I am in the process of redoing my will following DH's death and it will follow a similar format to what we agreed, ironically, just before his diagnosis. Each DD will inherit one third to be shared equally with any of their own DC. DD2 and DD3 are my executors but not DD1 as, sad to say, I don't completely trust her, certainly whilst she remains with LB, which is a terrible admission. As another poster has said, these situations do give rise to deep feelings of personal failure. Interestingly, DD1 did admit to a feeling of having failed in her relationships with her sisters, which was the nearest that there has been to any acknowledgement of the hurt caused. But since then she has obviously discussed matters with LB again and has clammed up and reverted to victim mode.
Gosh, this is a long post. My apologies!