I feel incredibly sorry for the sadness felt by the op. it’s a very sad situation for her, and in her situation I would feel equally upset.
However, i found your post very unsettling bluebell. I don’t think you’re understanding the all consuming grief of losing a spouse or partner at such a young age. The poor woman has lost everything, her husband, her children’s father and the future that she thought she was going to have. Her ‘hurtful’ behaviour sounds to me like a woman desperately trying to cling to the routine that she and her children had before they lost one of the most precious and important people in their lives.
I lost a partner, and for TWO years, I couldn’t bear anybody to be sitting in his chair once the clock turned 515, because that was when he was usually home. I asked people to move. Including my young son.
6 months after I’d lost my partner I got a call from my sons school. I was 30 minutes late picking him up, I’d got back into the bed that I shared with my partner, and had completely lost track of time. I have never felt so ashamed. It was a very kind school secretary who hugged me and said that if we weren't allowed to be selfish when we were suffering the worst grief imaginable, then when could we.
Now think of Mother’s day. The first mother’s day without your husband. The first mother’s day when perhaps, nobody had encouraged your young children to make you a card. Another morning where you wake up and realise that now, you’re alone, it really is just you who’s responsible for those children. You can’t help but wonder how they’re going to cope in a few months when Fathers Day comes around. And in that moment, when you believe that those children are all you have, you remember that your mil won’t be getting a card either, because she has just buried her son. Of course they gravitated together.
Yes in an ideal world she would have visited her mother too, but in a ideal world people in their 30s don’t lose their partners, and young children aren’t left without fathers.
This is a woman doing her best to not only cope with her own grief, but to help her children through it too.
My advice to the op, is to keep up contact, but gently. Send your daughter a text saying you love her, that you’re thinking of her. Pop a couple of colouring books through the door for the children to keep them busy. Maybe do the same for her mil, nip round with a bunch of flowers, let her know that you care. Maybe suggest to mil a day when you can all take the children to a park or something, it’ll do you all good.