Ah Shanti this is so tough. I went through similar many years ago when my niece and nephew went to live in the US.

I missed them terribly as up until then they spent holidays and occasional weekends with me and we were so close.

Luckily they were only away for about a year, but I remember clearly how sad I felt at the separation.

I am sure your nieces miss you terribly too. A loving aunty is a precious thing.

Christmas isn't so far away and that will be a joyous reunion I am sure.