yes do invite her so that the continuity is still there. She will be missing her husband very much of course, and facing first time doing things alone is very hard, as I know myself. But the longer you put it off the harder it gets, and so it will do two things. Firstly she is still your friend and is not being ignored or left out, and secondly at least she will have the comfort of facing those hard efforts of going alone for the first time with people she knows care for her. Then later , in the early part of january or february could you think of something that you could do together, in a situation that is not something that was connected with her husband. So it could be something like trying out a new activity , perhaps going swimming together, or to a quiz one evening, or does she enjoy something but rarely did it with her husband? So perhaps you might ask her round to play cards, bridge or whist or anything you can enjoy or a game of dominos, but making the invitation something for you all by saying something like "Oh we are fed up on these dark evenings thought we might play bridge (or whatever) do you fancy joining us? so that it is not seen as a pitying sort of an effort, just a genuine chance to share an evening together. It can be easy to do things over the holiday period and then there is that dark and miserable weather time where we often stay at home and do things and this is when it would be great if you could invite her on her own merit, rather than it being seen as making a special effort because of her circumstances. Keep being a good friend. They are like gold dust. I have a friend that I have known for 76 years now as we met when I was 2. I have lived abroad and done lots of things but always kept in touch and made sure to meet up when I was in England. It has been a great joy to have her in my life and when my husband died the fact that she had known him well meant a lot to me . May you have a happy christmas and may the new year bring you both pleasure in each others company