I am sorry for the delay in responding, I did start to reply yesterday, but I found it all quite painful to think about.
I will always love my DD, but I have been very hurt by her treatment of me and the rest of the family over the last few years. Quite apart from my own feelings, I have watched my DH suffer - his sad face when he sent messages that were without reply - and my younger DDs, who loved DD1 and basically still do, I think, as they were all close, but now don't even want to mention her. It has had a massive impact on our family and we have all tried to cope in our different ways. Also, and this saddens me a lot, my elderly MIL who was a big part of DD1's life growing up, has dementia which has deteriorated rapidly over the last year. It would have meant such a lot to her to know that she had a DGD and to have met her. Now I think that she sort of knows, but then she forgets - that lost 14 months, when none of us knew about DGD, would have made a huge difference in her knowing and not really knowing and rejoicing.
Despite all of that, and I do have some quite negative feelings about DD1 at the moment which I am struggling to come to terms with, I can't do anything but follow the path towards reconciliation, with all of its risks, including that of being badly hurt again. I have to take that risk, but it involves having to trust again, and that is what I am finding hard at times. That is why I started this thread. Thank you so much Bustpipes for your positive post about your reconciliation with your dad, which I found really helpful.
A number of you have raised questions as to why DD and SIL need financial support and Sprouts has asked some very pertinent questions about my motivation in doing so. My original decision to 'lend' the money to DD to buy the house has proved, with hindsight, to be wrong, but it did not seem so at the time. She and SIL wanted to stay in their university town, where house prices were still reasonable but rising quickly. Like many parents, I wanted to help her to get onto the housing ladder and, although she and SIL were young, they seemed happy, and to have good job prospects. Provided that the legal position was protected with a Deed of Trust, I did not see a risk or downside in helping her. Then I changed my mind for the reasons which I have explained up thread - DD at the time 'forgave' me very quickly, but SIL never has.
I feel that over the last four and a half years, SIL has infected DD with his own bitterness, so that she came round to the view that we were the 'bad' family compared with his 'good' family, and that we had let them down very badly. SIL feels that we owe them, that we need to 'make amends' and that, until we do, we should be excluded from their lives and those of DGC. I am as certain as I can be that this was the reason for the estrangement and why DD turned from a loving daughter to someone filled with resentment, especially against me. As regards DH, she told him that he hadn't done anything wrong, but he hadn't done anything right. So we were cut out - either as a punishment for letting them down or as a means of emotional blackmail to get us to change our minds, possibly a mixture of the two. Apart from the occasional telephone call and birthday card, there was virtually no contact and we did not know their new address, that they had married, or that we had a DGD.
The turning point came in a telephone conversation with DD last Christmas Day. She said how hurt she had been, that I had 'got the family', and asked why I had not proceeded with the house purchase and said that they had been 'scrimping and saving'. I explained and she seemed to be listening. She also spoke of wanting to do the PGCE course. She did not mention DGD, who would have been 6 months old then. I said that we would support her in doing the course. I thought that it would be good for her, that it would make her more independent in that, apart from having a highly prized skill and means of earning a living, she would hopefully move away from being with SIL 24/7, and would be open to different people and ideas. I also did have some 'guilt' at not making the original loan and a desire to change the narrative that we are the 'bad guys', to show our love and support for her.
Then we had the lunch about 6 months later, which went well, following which there was a request for the loan towards buying the house to let out. I was a bit taken aback that they were in a position to buy a second property as I though that they had been struggling, and disappointed at the timing - so soon after the first time we had seen DD in two and a half years - but we agreed. And yes, to be honest, part of the reason was that I wanted to rebuild the relationship with DD and was afraid that, if we refused, this might not happen.
And it has been the right move to the extent that we found out about DGD and the existing pregnancy, and there is not only a renewal of contact with DD, but she is in touch all of the time. I am certain that it is because she wants to be in touch, and I sense that she was also upset by the estrangement and missed us. I also think that, much as we suffered, it must also have been hard for her to go through pregnancy, an emergency C section, the first year of baby's life, and a week in hospital when her baby who had a life threatening condition, without any support from her DP.
There are so many good points which everyone has raised that I can't mention them all. However, Theo makes an excellent point that SIL, if not exactly lacking in self-respect, certainly has a very sensitive ego. He is very easily offended and, as Maybe said, probably the teaching profession is not ideal for him, as he doesn't like hierarchies and can't cope with criticism. Theo is also right in saying that, whatever our DC's choices, which we may not understand, 'it's not mine to get, or to bear'.
Maybe sums it up perfectly in saying that the relationship lasts because it is not currently subject to ordinary pressures, including financial pressures. As Kitty points out, this will change when DD relocates to do her course. SIL will have to pull his weight in order for things to succeed and 'keep the show on the road'. Will he be equal to the challenge? For DD's and DGDs' sake, I hope that he will, but honestly I have my doubts.
In answer to SirVix, we are hoping to meet the PIL when we visit in the new year, although I sense that DD and SIL are not that keen. DD said it might be a bit much for us in the first visit, to which I said we would just see how it goes. I am quite keen to meet them and we are thinking that we will invite them out for lunch or something and try to get to know them. I agree that it would be too much to see them at the same time as DD, SIL and DGDs.
Sorry this is long and that I may not have answered all of the points, but I am getting tired now and going back to bed. This has been cathartic and has helped clarify my thinking, so thank you very much to everybody who has contributed.