I think both 'a loving relationship' and 'banning' are extremes of behaviour, neither of which was Queen Mary's way. I'm not aware that after the abdication Queen Mary ever received the Duchess of Windsor, even privately, which created a certain distance between herself and her son which made things a little strained and awkward and contributed to the Duke's continuing resentment against the royal family. However, she did keep up a regular correspondence with her son and met the Duke in 1945 and Pope-Hennessy quotes her writing "David arrived by plane from Paris on a visit to me-I had not seen him for nearly 9 years! it was a great joy meeting again, he looked very well". Pope-Hennessy also quotes the letter to which I think royal netherlands refers, which she wrote to the Duke when the Duchess was ill in New York in 1951 to say "I feel so sorry for your great anxiety about your wife, and am thankful that so far you are able to send a fair account so we must hope the improvement will continue. Do write me a short account of what has really happened". She certainly continued to love him as her son, but her unrelenting stance against the Duchess was interpreted - and not only by the Duke - as cold and unforgiving. In fact I think the shock of the abdication was so great she simply could not bring herself to actually meet the Duchess, who no doubt she with her Victorian upbringing placed most of the blame upon for the whole business. In that attitude she wasn't being fair, of course, but then she wasn't being cold either.